splice the common libc functions and ctypes throughout the library

18 files changed, 1002 insertions, 256 deletions

diff --git a/src/cloudabi/mod.rs b/src/cloudabi/mod.rs
index e506414e34..f72eeb4d24 100644
--- a/src/cloudabi/mod.rs
+++ b/src/cloudabi/mod.rs
@@ -1,3 +1,32 @@
+
+pub type int8_t = i8;
+pub type int16_t = i16;
+pub type int32_t = i32;
+pub type int64_t = i64;
+pub type uint8_t = u8;
+pub type uint16_t = u16;
+pub type uint32_t = u32;
+pub type uint64_t = u64;
+
+pub type c_schar = i8;
+pub type c_uchar = u8;
+pub type c_short = i16;
+pub type c_ushort = u16;
+pub type c_int = i32;
+pub type c_uint = u32;
+pub type c_float = f32;
+pub type c_double = f64;
+pub type c_longlong = i64;
+pub type c_ulonglong = u64;
+pub type intmax_t = i64;
+pub type uintmax_t = u64;
+
+pub type size_t = usize;
+pub type ptrdiff_t = isize;
+pub type intptr_t = isize;
+pub type uintptr_t = usize;
+pub type ssize_t = isize;
+
 pub type in_addr_t = u32;
 pub type in_port_t = u16;
 pub type pthread_key_t = usize;
@@ -56,6 +85,9 @@ s! {
     }
 }
 
+pub const INT_MIN: c_int = -2147483648;
+pub const INT_MAX: c_int = 2147483647;
+
 pub const _SC_NPROCESSORS_ONLN: ::c_int = 52;
 pub const _SC_PAGESIZE: ::c_int = 54;
 
@@ -89,7 +121,109 @@ pub const PTHREAD_STACK_MIN: ::size_t = 1024;
 pub const SOCK_DGRAM: ::c_int = 128;
 pub const SOCK_STREAM: ::c_int = 130;
 
+pub enum FILE {}
+pub enum fpos_t {} // TODO: fill this out with a struct
+
 extern {
+    pub fn isalnum(c: c_int) -> c_int;
+    pub fn isalpha(c: c_int) -> c_int;
+    pub fn iscntrl(c: c_int) -> c_int;
+    pub fn isdigit(c: c_int) -> c_int;
+    pub fn isgraph(c: c_int) -> c_int;
+    pub fn islower(c: c_int) -> c_int;
+    pub fn isprint(c: c_int) -> c_int;
+    pub fn ispunct(c: c_int) -> c_int;
+    pub fn isspace(c: c_int) -> c_int;
+    pub fn isupper(c: c_int) -> c_int;
+    pub fn isxdigit(c: c_int) -> c_int;
+    pub fn tolower(c: c_int) -> c_int;
+    pub fn toupper(c: c_int) -> c_int;
+    pub fn fopen(filename: *const c_char, mode: *const c_char) -> *mut FILE;
+    pub fn freopen(filename: *const c_char, mode: *const c_char,
+                   file: *mut FILE) -> *mut FILE;
+    pub fn fflush(file: *mut FILE) -> c_int;
+    pub fn fclose(file: *mut FILE) -> c_int;
+    pub fn remove(filename: *const c_char) -> c_int;
+    pub fn rename(oldname: *const c_char, newname: *const c_char) -> c_int;
+    pub fn tmpfile() -> *mut FILE;
+    pub fn setvbuf(stream: *mut FILE, buffer: *mut c_char, mode: c_int,
+                   size: size_t) -> c_int;
+    pub fn setbuf(stream: *mut FILE, buf: *mut c_char);
+    pub fn getchar() -> c_int;
+    pub fn putchar(c: c_int) -> c_int;
+    pub fn fgetc(stream: *mut FILE) -> c_int;
+    pub fn fgets(buf: *mut c_char, n: c_int, stream: *mut FILE) -> *mut c_char;
+    pub fn fputc(c: c_int, stream: *mut FILE) -> c_int;
+    pub fn fputs(s: *const c_char, stream: *mut FILE) -> c_int;
+    pub fn puts(s: *const c_char) -> c_int;
+    pub fn ungetc(c: c_int, stream: *mut FILE) -> c_int;
+    pub fn fread(ptr: *mut c_void, size: size_t, nobj: size_t,
+                 stream: *mut FILE) -> size_t;
+    pub fn fwrite(ptr: *const c_void, size: size_t, nobj: size_t,
+                  stream: *mut FILE) -> size_t;
+    pub fn fseek(stream: *mut FILE, offset: c_long, whence: c_int) -> c_int;
+    pub fn ftell(stream: *mut FILE) -> c_long;
+    pub fn rewind(stream: *mut FILE);
+    pub fn fgetpos(stream: *mut FILE, ptr: *mut fpos_t) -> c_int;
+    pub fn fsetpos(stream: *mut FILE, ptr: *const fpos_t) -> c_int;
+    pub fn feof(stream: *mut FILE) -> c_int;
+    pub fn ferror(stream: *mut FILE) -> c_int;
+    pub fn perror(s: *const c_char);
+    pub fn atoi(s: *const c_char) -> c_int;
+    pub fn strtod(s: *const c_char, endp: *mut *mut c_char) -> c_double;
+    pub fn strtol(s: *const c_char, endp: *mut *mut c_char,
+                  base: c_int) -> c_long;
+    pub fn strtoul(s: *const c_char, endp: *mut *mut c_char,
+                   base: c_int) -> c_ulong;
+    pub fn calloc(nobj: size_t, size: size_t) -> *mut c_void;
+    pub fn malloc(size: size_t) -> *mut c_void;
+    pub fn realloc(p: *mut c_void, size: size_t) -> *mut c_void;
+    pub fn free(p: *mut c_void);
+    pub fn abort() -> !;
+    pub fn exit(status: c_int) -> !;
+    pub fn _exit(status: c_int) -> !;
+    pub fn atexit(cb: extern fn()) -> c_int;
+    pub fn system(s: *const c_char) -> c_int;
+    pub fn getenv(s: *const c_char) -> *mut c_char;
+
+    pub fn strcpy(dst: *mut c_char, src: *const c_char) -> *mut c_char;
+    pub fn strncpy(dst: *mut c_char, src: *const c_char,
+                   n: size_t) -> *mut c_char;
+    pub fn strcat(s: *mut c_char, ct: *const c_char) -> *mut c_char;
+    pub fn strncat(s: *mut c_char, ct: *const c_char, n: size_t) -> *mut c_char;
+    pub fn strcmp(cs: *const c_char, ct: *const c_char) -> c_int;
+    pub fn strncmp(cs: *const c_char, ct: *const c_char, n: size_t) -> c_int;
+    pub fn strcoll(cs: *const c_char, ct: *const c_char) -> c_int;
+    pub fn strchr(cs: *const c_char, c: c_int) -> *mut c_char;
+    pub fn strrchr(cs: *const c_char, c: c_int) -> *mut c_char;
+    pub fn strspn(cs: *const c_char, ct: *const c_char) -> size_t;
+    pub fn strcspn(cs: *const c_char, ct: *const c_char) -> size_t;
+    pub fn strdup(cs: *const c_char) -> *mut c_char;
+    pub fn strpbrk(cs: *const c_char, ct: *const c_char) -> *mut c_char;
+    pub fn strstr(cs: *const c_char, ct: *const c_char) -> *mut c_char;
+    pub fn strlen(cs: *const c_char) -> size_t;
+    pub fn strnlen(cs: *const c_char, maxlen: size_t) -> size_t;
+    pub fn strerror(n: c_int) -> *mut c_char;
+    pub fn strtok(s: *mut c_char, t: *const c_char) -> *mut c_char;
+    pub fn strxfrm(s: *mut c_char, ct: *const c_char, n: size_t) -> size_t;
+    pub fn wcslen(buf: *const wchar_t) -> size_t;
+    pub fn wcstombs(dest: *mut c_char, src: *const wchar_t,
+                    n: size_t) -> ::size_t;
+
+    pub fn memchr(cx: *const c_void, c: c_int, n: size_t) -> *mut c_void;
+    pub fn memcmp(cx: *const c_void, ct: *const c_void, n: size_t) -> c_int;
+    pub fn memcpy(dest: *mut c_void, src: *const c_void,
+                  n: size_t) -> *mut c_void;
+    pub fn memmove(dest: *mut c_void, src: *const c_void,
+                   n: size_t) -> *mut c_void;
+    pub fn memset(dest: *mut c_void, c: c_int, n: size_t) -> *mut c_void;
+
+    pub fn abs(i: c_int) -> c_int;
+    pub fn atof(s: *const c_char) -> c_double;
+    pub fn labs(i: c_long) -> c_long;
+    pub fn rand() -> c_int;
+    pub fn srand(seed: c_uint);
+
     pub fn arc4random_buf(buf: *const ::c_void, len: ::size_t);
     pub fn freeaddrinfo(res: *mut addrinfo);
     pub fn gai_strerror(errcode: ::c_int) -> *const ::c_char;
@@ -164,3 +298,21 @@ cfg_if! {
         // Unknown target_arch
     }
 }
+
+cfg_if! {
+    if #[cfg(core_cvoid)] {
+        pub use core::ffi::c_void;
+    } else {
+        // Use repr(u8) as LLVM expects `void*` to be the same as `i8*` to help
+        // enable more optimization opportunities around it recognizing things
+        // like malloc/free.
+        #[repr(u8)]
+        pub enum c_void {
+            // Two dummy variants so the #[repr] attribute can be used.
+            #[doc(hidden)]
+            __variant1,
+            #[doc(hidden)]
+            __variant2,
+        }
+    }
+}
diff --git a/src/ctypes.rs b/src/ctypes.rs
deleted file mode 100644
index aebbfb774f..0000000000
--- a/src/ctypes.rs
+++ /dev/null
@@ -1,50 +0,0 @@
-//! Common libc types
-
-cfg_if! {
-    if #[cfg(core_cvoid)] {
-        pub use core::ffi::c_void;
-    } else {
-        // Use repr(u8) as LLVM expects `void*` to be the same as `i8*` to help enable
-        // more optimization opportunities around it recognizing things like
-        // malloc/free.
-        #[repr(u8)]
-        pub enum c_void {
-            // Two dummy variants so the #[repr] attribute can be used.
-            #[doc(hidden)]
-            __variant1,
-            #[doc(hidden)]
-            __variant2,
-        }
-    }
-}
-
-pub type int8_t = i8;
-pub type int16_t = i16;
-pub type int32_t = i32;
-pub type int64_t = i64;
-pub type uint8_t = u8;
-pub type uint16_t = u16;
-pub type uint32_t = u32;
-pub type uint64_t = u64;
-
-pub type c_schar = i8;
-pub type c_uchar = u8;
-pub type c_short = i16;
-pub type c_ushort = u16;
-pub type c_int = i32;
-pub type c_uint = u32;
-pub type c_float = f32;
-pub type c_double = f64;
-pub type c_longlong = i64;
-pub type c_ulonglong = u64;
-pub type intmax_t = i64;
-pub type uintmax_t = u64;
-
-pub type size_t = usize;
-pub type ptrdiff_t = isize;
-pub type intptr_t = isize;
-pub type uintptr_t = usize;
-pub type ssize_t = isize;
-
-pub const INT_MIN: c_int = -2147483648;
-pub const INT_MAX: c_int = 2147483647;
diff --git a/src/fuchsia/mod.rs b/src/fuchsia/mod.rs
index 7c1d1a4976..deb1c5d95f 100644
--- a/src/fuchsia/mod.rs
+++ b/src/fuchsia/mod.rs
@@ -7,6 +7,34 @@ use dox::{mem, Option};
 
 // PUB_TYPE
 
+pub type int8_t = i8;
+pub type int16_t = i16;
+pub type int32_t = i32;
+pub type int64_t = i64;
+pub type uint8_t = u8;
+pub type uint16_t = u16;
+pub type uint32_t = u32;
+pub type uint64_t = u64;
+
+pub type c_schar = i8;
+pub type c_uchar = u8;
+pub type c_short = i16;
+pub type c_ushort = u16;
+pub type c_int = i32;
+pub type c_uint = u32;
+pub type c_float = f32;
+pub type c_double = f64;
+pub type c_longlong = i64;
+pub type c_ulonglong = u64;
+pub type intmax_t = i64;
+pub type uintmax_t = u64;
+
+pub type size_t = usize;
+pub type ptrdiff_t = isize;
+pub type intptr_t = isize;
+pub type uintptr_t = usize;
+pub type ssize_t = isize;
+
 pub type pid_t = i32;
 pub type uid_t = u32;
 pub type gid_t = u32;
@@ -1049,6 +1077,9 @@ s! {
 
 // PUB_CONST
 
+pub const INT_MIN: c_int = -2147483648;
+pub const INT_MAX: c_int = 2147483647;
+
 pub const SIG_DFL: sighandler_t = 0 as sighandler_t;
 pub const SIG_IGN: sighandler_t = 1 as sighandler_t;
 pub const SIG_ERR: sighandler_t = !0 as sighandler_t;
@@ -3011,7 +3042,110 @@ f! {
 #[link(name = "fdio")]
 extern {}
 
+pub enum FILE {}
+pub enum fpos_t {} // TODO: fill this out with a struct
+
 extern {
+    pub fn isalnum(c: c_int) -> c_int;
+    pub fn isalpha(c: c_int) -> c_int;
+    pub fn iscntrl(c: c_int) -> c_int;
+    pub fn isdigit(c: c_int) -> c_int;
+    pub fn isgraph(c: c_int) -> c_int;
+    pub fn islower(c: c_int) -> c_int;
+    pub fn isprint(c: c_int) -> c_int;
+    pub fn ispunct(c: c_int) -> c_int;
+    pub fn isspace(c: c_int) -> c_int;
+    pub fn isupper(c: c_int) -> c_int;
+    pub fn isxdigit(c: c_int) -> c_int;
+    pub fn tolower(c: c_int) -> c_int;
+    pub fn toupper(c: c_int) -> c_int;
+    pub fn fopen(filename: *const c_char, mode: *const c_char) -> *mut FILE;
+    pub fn freopen(filename: *const c_char, mode: *const c_char,
+                   file: *mut FILE) -> *mut FILE;
+    pub fn fflush(file: *mut FILE) -> c_int;
+    pub fn fclose(file: *mut FILE) -> c_int;
+    pub fn remove(filename: *const c_char) -> c_int;
+    pub fn rename(oldname: *const c_char, newname: *const c_char) -> c_int;
+    pub fn tmpfile() -> *mut FILE;
+    pub fn setvbuf(stream: *mut FILE, buffer: *mut c_char, mode: c_int,
+                   size: size_t) -> c_int;
+    pub fn setbuf(stream: *mut FILE, buf: *mut c_char);
+    pub fn getchar() -> c_int;
+    pub fn putchar(c: c_int) -> c_int;
+    pub fn fgetc(stream: *mut FILE) -> c_int;
+    pub fn fgets(buf: *mut c_char, n: c_int, stream: *mut FILE) -> *mut c_char;
+    pub fn fputc(c: c_int, stream: *mut FILE) -> c_int;
+    pub fn fputs(s: *const c_char, stream: *mut FILE) -> c_int;
+    pub fn puts(s: *const c_char) -> c_int;
+    pub fn ungetc(c: c_int, stream: *mut FILE) -> c_int;
+    pub fn fread(ptr: *mut c_void, size: size_t, nobj: size_t,
+                 stream: *mut FILE) -> size_t;
+    pub fn fwrite(ptr: *const c_void, size: size_t, nobj: size_t,
+                  stream: *mut FILE) -> size_t;
+    pub fn fseek(stream: *mut FILE, offset: c_long, whence: c_int) -> c_int;
+    pub fn ftell(stream: *mut FILE) -> c_long;
+    pub fn rewind(stream: *mut FILE);
+    pub fn fgetpos(stream: *mut FILE, ptr: *mut fpos_t) -> c_int;
+    pub fn fsetpos(stream: *mut FILE, ptr: *const fpos_t) -> c_int;
+    pub fn feof(stream: *mut FILE) -> c_int;
+    pub fn ferror(stream: *mut FILE) -> c_int;
+    pub fn perror(s: *const c_char);
+    pub fn atoi(s: *const c_char) -> c_int;
+    pub fn strtod(s: *const c_char, endp: *mut *mut c_char) -> c_double;
+    pub fn strtol(s: *const c_char, endp: *mut *mut c_char,
+                  base: c_int) -> c_long;
+    pub fn strtoul(s: *const c_char, endp: *mut *mut c_char,
+                   base: c_int) -> c_ulong;
+    pub fn calloc(nobj: size_t, size: size_t) -> *mut c_void;
+    pub fn malloc(size: size_t) -> *mut c_void;
+    pub fn realloc(p: *mut c_void, size: size_t) -> *mut c_void;
+    pub fn free(p: *mut c_void);
+    pub fn abort() -> !;
+    pub fn exit(status: c_int) -> !;
+    pub fn _exit(status: c_int) -> !;
+    pub fn atexit(cb: extern fn()) -> c_int;
+    pub fn system(s: *const c_char) -> c_int;
+    pub fn getenv(s: *const c_char) -> *mut c_char;
+
+    pub fn strcpy(dst: *mut c_char, src: *const c_char) -> *mut c_char;
+    pub fn strncpy(dst: *mut c_char, src: *const c_char,
+                   n: size_t) -> *mut c_char;
+    pub fn strcat(s: *mut c_char, ct: *const c_char) -> *mut c_char;
+    pub fn strncat(s: *mut c_char, ct: *const c_char,
+                   n: size_t) -> *mut c_char;
+    pub fn strcmp(cs: *const c_char, ct: *const c_char) -> c_int;
+    pub fn strncmp(cs: *const c_char, ct: *const c_char, n: size_t) -> c_int;
+    pub fn strcoll(cs: *const c_char, ct: *const c_char) -> c_int;
+    pub fn strchr(cs: *const c_char, c: c_int) -> *mut c_char;
+    pub fn strrchr(cs: *const c_char, c: c_int) -> *mut c_char;
+    pub fn strspn(cs: *const c_char, ct: *const c_char) -> size_t;
+    pub fn strcspn(cs: *const c_char, ct: *const c_char) -> size_t;
+    pub fn strdup(cs: *const c_char) -> *mut c_char;
+    pub fn strpbrk(cs: *const c_char, ct: *const c_char) -> *mut c_char;
+    pub fn strstr(cs: *const c_char, ct: *const c_char) -> *mut c_char;
+    pub fn strlen(cs: *const c_char) -> size_t;
+    pub fn strnlen(cs: *const c_char, maxlen: size_t) -> size_t;
+    pub fn strerror(n: c_int) -> *mut c_char;
+    pub fn strtok(s: *mut c_char, t: *const c_char) -> *mut c_char;
+    pub fn strxfrm(s: *mut c_char, ct: *const c_char, n: size_t) -> size_t;
+    pub fn wcslen(buf: *const wchar_t) -> size_t;
+    pub fn wcstombs(dest: *mut c_char, src: *const wchar_t,
+                    n: size_t) -> ::size_t;
+
+    pub fn memchr(cx: *const c_void, c: c_int, n: size_t) -> *mut c_void;
+    pub fn memcmp(cx: *const c_void, ct: *const c_void, n: size_t) -> c_int;
+    pub fn memcpy(dest: *mut c_void, src: *const c_void,
+                  n: size_t) -> *mut c_void;
+    pub fn memmove(dest: *mut c_void, src: *const c_void,
+                   n: size_t) -> *mut c_void;
+    pub fn memset(dest: *mut c_void, c: c_int, n: size_t) -> *mut c_void;
+
+    pub fn abs(i: c_int) -> c_int;
+    pub fn atof(s: *const c_char) -> c_double;
+    pub fn labs(i: c_long) -> c_long;
+    pub fn rand() -> c_int;
+    pub fn srand(seed: c_uint);
+
     pub fn getpwnam(name: *const ::c_char) -> *mut passwd;
     pub fn getpwuid(uid: ::uid_t) -> *mut passwd;
 
@@ -3953,3 +4087,21 @@ cfg_if! {
         // Unknown target_arch
     }
 }
+
+cfg_if! {
+    if #[cfg(core_cvoid)] {
+        pub use core::ffi::c_void;
+    } else {
+        // Use repr(u8) as LLVM expects `void*` to be the same as `i8*` to help
+        // enable more optimization opportunities around it recognizing things
+        // like malloc/free.
+        #[repr(u8)]
+        pub enum c_void {
+            // Two dummy variants so the #[repr] attribute can be used.
+            #[doc(hidden)]
+            __variant1,
+            #[doc(hidden)]
+            __variant2,
+        }
+    }
+}
diff --git a/src/lib.rs b/src/lib.rs
index c8beeedccd..54f67895a6 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -21,31 +21,45 @@
 )]
 #![cfg_attr(
     all(target_os = "linux", target_arch = "x86_64"),
-    doc(html_root_url = "https://rust-lang.github.io/libc/x86_64-unknown-linux-gnu")
+    doc(
+        html_root_url = "https://rust-lang.github.io/libc/x86_64-unknown-linux-gnu"
+    )
 )]
 #![cfg_attr(
     all(target_os = "linux", target_arch = "x86"),
-    doc(html_root_url = "https://rust-lang.github.io/libc/i686-unknown-linux-gnu")
+    doc(
+        html_root_url = "https://rust-lang.github.io/libc/i686-unknown-linux-gnu"
+    )
 )]
 #![cfg_attr(
     all(target_os = "linux", target_arch = "arm"),
-    doc(html_root_url = "https://rust-lang.github.io/libc/arm-unknown-linux-gnueabihf")
+    doc(
+        html_root_url = "https://rust-lang.github.io/libc/arm-unknown-linux-gnueabihf"
+    )
 )]
 #![cfg_attr(
     all(target_os = "linux", target_arch = "mips"),
-    doc(html_root_url = "https://rust-lang.github.io/libc/mips-unknown-linux-gnu")
+    doc(
+        html_root_url = "https://rust-lang.github.io/libc/mips-unknown-linux-gnu"
+    )
 )]
 #![cfg_attr(
     all(target_os = "linux", target_arch = "aarch64"),
-    doc(html_root_url = "https://rust-lang.github.io/libc/aarch64-unknown-linux-gnu")
+    doc(
+        html_root_url = "https://rust-lang.github.io/libc/aarch64-unknown-linux-gnu"
+    )
 )]
 #![cfg_attr(
     all(target_os = "linux", target_env = "musl"),
-    doc(html_root_url = "https://rust-lang.github.io/libc/x86_64-unknown-linux-musl")
+    doc(
+        html_root_url = "https://rust-lang.github.io/libc/x86_64-unknown-linux-musl"
+    )
 )]
 #![cfg_attr(
     all(target_os = "macos", target_arch = "x86_64"),
-    doc(html_root_url = "https://rust-lang.github.io/libc/x86_64-apple-darwin")
+    doc(
+        html_root_url = "https://rust-lang.github.io/libc/x86_64-apple-darwin"
+    )
 )]
 #![cfg_attr(
     all(target_os = "macos", target_arch = "x86"),
@@ -53,59 +67,87 @@
 )]
 #![cfg_attr(
     all(windows, target_arch = "x86_64", target_env = "gnu"),
-    doc(html_root_url = "https://rust-lang.github.io/libc/x86_64-pc-windows-gnu")
+    doc(
+        html_root_url = "https://rust-lang.github.io/libc/x86_64-pc-windows-gnu"
+    )
 )]
 #![cfg_attr(
     all(windows, target_arch = "x86", target_env = "gnu"),
-    doc(html_root_url = "https://rust-lang.github.io/libc/i686-pc-windows-gnu")
+    doc(
+        html_root_url = "https://rust-lang.github.io/libc/i686-pc-windows-gnu"
+    )
 )]
 #![cfg_attr(
     all(windows, target_arch = "x86_64", target_env = "msvc"),
-    doc(html_root_url = "https://rust-lang.github.io/libc/x86_64-pc-windows-msvc")
+    doc(
+        html_root_url = "https://rust-lang.github.io/libc/x86_64-pc-windows-msvc"
+    )
 )]
 #![cfg_attr(
     all(windows, target_arch = "x86", target_env = "msvc"),
-    doc(html_root_url = "https://rust-lang.github.io/libc/i686-pc-windows-msvc")
+    doc(
+        html_root_url = "https://rust-lang.github.io/libc/i686-pc-windows-msvc"
+    )
 )]
 #![cfg_attr(
     target_os = "android",
-    doc(html_root_url = "https://rust-lang.github.io/libc/arm-linux-androideabi")
+    doc(
+        html_root_url = "https://rust-lang.github.io/libc/arm-linux-androideabi"
+    )
 )]
 #![cfg_attr(
     target_os = "freebsd",
-    doc(html_root_url = "https://rust-lang.github.io/libc/x86_64-unknown-freebsd")
+    doc(
+        html_root_url = "https://rust-lang.github.io/libc/x86_64-unknown-freebsd"
+    )
 )]
 #![cfg_attr(
     target_os = "openbsd",
-    doc(html_root_url = "https://rust-lang.github.io/libc/x86_64-unknown-openbsd")
+    doc(
+        html_root_url = "https://rust-lang.github.io/libc/x86_64-unknown-openbsd"
+    )
 )]
 #![cfg_attr(
     target_os = "bitrig",
-    doc(html_root_url = "https://rust-lang.github.io/libc/x86_64-unknown-bitrig")
+    doc(
+        html_root_url = "https://rust-lang.github.io/libc/x86_64-unknown-bitrig"
+    )
 )]
 #![cfg_attr(
     target_os = "netbsd",
-    doc(html_root_url = "https://rust-lang.github.io/libc/x86_64-unknown-netbsd")
+    doc(
+        html_root_url = "https://rust-lang.github.io/libc/x86_64-unknown-netbsd"
+    )
 )]
 #![cfg_attr(
     target_os = "dragonfly",
-    doc(html_root_url = "https://rust-lang.github.io/libc/x86_64-unknown-dragonfly")
+    doc(
+        html_root_url = "https://rust-lang.github.io/libc/x86_64-unknown-dragonfly"
+    )
 )]
 #![cfg_attr(
     target_os = "solaris",
-    doc(html_root_url = "https://rust-lang.github.io/libc/x86_64-sun-solaris")
+    doc(
+        html_root_url = "https://rust-lang.github.io/libc/x86_64-sun-solaris"
+    )
 )]
 #![cfg_attr(
     all(target_os = "emscripten", target_arch = "asmjs"),
-    doc(html_root_url = "https://rust-lang.github.io/libc/asmjs-unknown-emscripten")
+    doc(
+        html_root_url = "https://rust-lang.github.io/libc/asmjs-unknown-emscripten"
+    )
 )]
 #![cfg_attr(
     all(target_os = "emscripten", target_arch = "wasm32"),
-    doc(html_root_url = "https://rust-lang.github.io/libc/wasm32-unknown-emscripten")
+    doc(
+        html_root_url = "https://rust-lang.github.io/libc/wasm32-unknown-emscripten"
+    )
 )]
 #![cfg_attr(
     all(target_os = "linux", target_arch = "sparc64"),
-    doc(html_root_url = "https://rust-lang.github.io/libc/sparc64-unknown-linux-gnu")
+    doc(
+        html_root_url = "https://rust-lang.github.io/libc/sparc64-unknown-linux-gnu"
+    )
 )]
 // Attributes needed when building as part of the standard library
 #![cfg_attr(feature = "stdbuild", feature(staged_api, cfg_target_vendor))]
@@ -131,76 +173,27 @@ mod dox;
 
 cfg_if! {
     if #[cfg(windows)] {
-        mod libc;
-        pub use libc::*;
-
-        mod ctypes;
-        pub use ctypes::*;
-
         mod windows;
         pub use windows::*;
     } else if #[cfg(target_os = "redox")] {
-        mod libc;
-        pub use libc::*;
-
-        mod ctypes;
-        pub use ctypes::*;
-
         mod redox;
         pub use redox::*;
     } else if #[cfg(target_os = "cloudabi")] {
-        mod libc;
-        pub use libc::*;
-
-        mod ctypes;
-        pub use ctypes::*;
-
         mod cloudabi;
         pub use cloudabi::*;
     } else if #[cfg(target_os = "fuchsia")] {
-        mod libc;
-        pub use libc::*;
-
-        mod ctypes;
-        pub use ctypes::*;
-
         mod fuchsia;
         pub use fuchsia::*;
     } else if #[cfg(target_os = "switch")] {
-        mod ctypes;
-        pub use ctypes::*;
-
         mod switch;
         pub use switch::*;
     } else if #[cfg(unix)] {
-        mod libc;
-        pub use libc::*;
-
-        mod ctypes;
-        pub use ctypes::*;
-
         mod unix;
         pub use unix::*;
     } else if #[cfg(target_env = "sgx")] {
-        mod ctypes;
-        pub use ctypes::*;
-
         mod sgx;
         pub use sgx::*;
-    } else if #[cfg(target_os = "emscripten")] {
-        mod libc;
-        pub use libc::*;
-
-        mod ctypes;
-        pub use ctypes::*;
-    } else if #[cfg(all(target_arch = "wasm32",
-                        target_env = "unknown"))] {
-        // wasm32-unknown-unknown
-    } else {
-        mod libc;
-        pub use libc::*;
-
-        mod ctypes;
-        pub use ctypes::*;
+    }  else {
+        // non-supported targets: empty...
     }
 }
diff --git a/src/libc.rs b/src/libc.rs
deleted file mode 100644
index 6f4aa3b53b..0000000000
--- a/src/libc.rs
+++ /dev/null
@@ -1,134 +0,0 @@
-//! Common libc APIs
-
-use ::{c_int, c_uint, c_void, c_double, size_t, wchar_t, c_char, c_long, c_ulong};
-
-pub enum FILE {}
-pub enum fpos_t {} // TODO: fill this out with a struct
-
-extern "C" {
-    pub fn isalnum(c: c_int) -> c_int;
-    pub fn isalpha(c: c_int) -> c_int;
-    pub fn iscntrl(c: c_int) -> c_int;
-    pub fn isdigit(c: c_int) -> c_int;
-    pub fn isgraph(c: c_int) -> c_int;
-    pub fn islower(c: c_int) -> c_int;
-    pub fn isprint(c: c_int) -> c_int;
-    pub fn ispunct(c: c_int) -> c_int;
-    pub fn isspace(c: c_int) -> c_int;
-    pub fn isupper(c: c_int) -> c_int;
-    pub fn isxdigit(c: c_int) -> c_int;
-    pub fn tolower(c: c_int) -> c_int;
-    pub fn toupper(c: c_int) -> c_int;
-
-    #[cfg_attr(
-        all(target_os = "macos", target_arch = "x86"),
-        link_name = "fopen$UNIX2003"
-    )]
-    pub fn fopen(filename: *const c_char, mode: *const c_char) -> *mut FILE;
-    #[cfg_attr(
-        all(target_os = "macos", target_arch = "x86"),
-        link_name = "freopen$UNIX2003"
-    )]
-    pub fn freopen(filename: *const c_char, mode: *const c_char, file: *mut FILE) -> *mut FILE;
-    pub fn fflush(file: *mut FILE) -> c_int;
-    pub fn fclose(file: *mut FILE) -> c_int;
-    pub fn remove(filename: *const c_char) -> c_int;
-    pub fn rename(oldname: *const c_char, newname: *const c_char) -> c_int;
-    pub fn tmpfile() -> *mut FILE;
-    pub fn setvbuf(stream: *mut FILE, buffer: *mut c_char, mode: c_int, size: size_t) -> c_int;
-    pub fn setbuf(stream: *mut FILE, buf: *mut c_char);
-    pub fn getchar() -> c_int;
-    pub fn putchar(c: c_int) -> c_int;
-    pub fn fgetc(stream: *mut FILE) -> c_int;
-    pub fn fgets(buf: *mut c_char, n: c_int, stream: *mut FILE) -> *mut c_char;
-    pub fn fputc(c: c_int, stream: *mut FILE) -> c_int;
-    #[cfg_attr(
-        all(target_os = "macos", target_arch = "x86"),
-        link_name = "fputs$UNIX2003"
-    )]
-    pub fn fputs(s: *const c_char, stream: *mut FILE) -> c_int;
-    pub fn puts(s: *const c_char) -> c_int;
-    pub fn ungetc(c: c_int, stream: *mut FILE) -> c_int;
-    pub fn fread(ptr: *mut c_void, size: size_t, nobj: size_t, stream: *mut FILE) -> size_t;
-    #[cfg_attr(
-        all(target_os = "macos", target_arch = "x86"),
-        link_name = "fwrite$UNIX2003"
-    )]
-    pub fn fwrite(ptr: *const c_void, size: size_t, nobj: size_t, stream: *mut FILE) -> size_t;
-    pub fn fseek(stream: *mut FILE, offset: c_long, whence: c_int) -> c_int;
-    pub fn ftell(stream: *mut FILE) -> c_long;
-    pub fn rewind(stream: *mut FILE);
-    #[cfg_attr(target_os = "netbsd", link_name = "__fgetpos50")]
-    pub fn fgetpos(stream: *mut FILE, ptr: *mut fpos_t) -> c_int;
-    #[cfg_attr(target_os = "netbsd", link_name = "__fsetpos50")]
-    pub fn fsetpos(stream: *mut FILE, ptr: *const fpos_t) -> c_int;
-    pub fn feof(stream: *mut FILE) -> c_int;
-    pub fn ferror(stream: *mut FILE) -> c_int;
-    pub fn perror(s: *const c_char);
-    pub fn atoi(s: *const c_char) -> c_int;
-    #[cfg_attr(
-        all(target_os = "macos", target_arch = "x86"),
-        link_name = "strtod$UNIX2003"
-    )]
-    pub fn strtod(s: *const c_char, endp: *mut *mut c_char) -> c_double;
-    pub fn strtol(s: *const c_char, endp: *mut *mut c_char, base: c_int) -> c_long;
-    pub fn strtoul(s: *const c_char, endp: *mut *mut c_char, base: c_int) -> c_ulong;
-    pub fn calloc(nobj: size_t, size: size_t) -> *mut c_void;
-    pub fn malloc(size: size_t) -> *mut c_void;
-    pub fn realloc(p: *mut c_void, size: size_t) -> *mut c_void;
-    pub fn free(p: *mut c_void);
-    pub fn abort() -> !;
-    pub fn exit(status: c_int) -> !;
-    pub fn _exit(status: c_int) -> !;
-    pub fn atexit(cb: extern "C" fn()) -> c_int;
-    #[cfg_attr(
-        all(target_os = "macos", target_arch = "x86"),
-        link_name = "system$UNIX2003"
-    )]
-    pub fn system(s: *const c_char) -> c_int;
-    pub fn getenv(s: *const c_char) -> *mut c_char;
-
-    pub fn strcpy(dst: *mut c_char, src: *const c_char) -> *mut c_char;
-    pub fn strncpy(dst: *mut c_char, src: *const c_char, n: size_t) -> *mut c_char;
-    pub fn strcat(s: *mut c_char, ct: *const c_char) -> *mut c_char;
-    pub fn strncat(s: *mut c_char, ct: *const c_char, n: size_t) -> *mut c_char;
-    pub fn strcmp(cs: *const c_char, ct: *const c_char) -> c_int;
-    pub fn strncmp(cs: *const c_char, ct: *const c_char, n: size_t) -> c_int;
-    pub fn strcoll(cs: *const c_char, ct: *const c_char) -> c_int;
-    pub fn strchr(cs: *const c_char, c: c_int) -> *mut c_char;
-    pub fn strrchr(cs: *const c_char, c: c_int) -> *mut c_char;
-    pub fn strspn(cs: *const c_char, ct: *const c_char) -> size_t;
-    pub fn strcspn(cs: *const c_char, ct: *const c_char) -> size_t;
-    pub fn strdup(cs: *const c_char) -> *mut c_char;
-    pub fn strpbrk(cs: *const c_char, ct: *const c_char) -> *mut c_char;
-    pub fn strstr(cs: *const c_char, ct: *const c_char) -> *mut c_char;
-    pub fn strlen(cs: *const c_char) -> size_t;
-    pub fn strnlen(cs: *const c_char, maxlen: size_t) -> size_t;
-    #[cfg_attr(
-        all(target_os = "macos", target_arch = "x86"),
-        link_name = "strerror$UNIX2003"
-    )]
-    pub fn strerror(n: c_int) -> *mut c_char;
-    pub fn strtok(s: *mut c_char, t: *const c_char) -> *mut c_char;
-    pub fn strxfrm(s: *mut c_char, ct: *const c_char, n: size_t) -> size_t;
-    pub fn wcslen(buf: *const wchar_t) -> size_t;
-    pub fn wcstombs(dest: *mut c_char, src: *const wchar_t, n: size_t) -> ::size_t;
-
-    pub fn memchr(cx: *const c_void, c: c_int, n: size_t) -> *mut c_void;
-    pub fn memcmp(cx: *const c_void, ct: *const c_void, n: size_t) -> c_int;
-    pub fn memcpy(dest: *mut c_void, src: *const c_void, n: size_t) -> *mut c_void;
-    pub fn memmove(dest: *mut c_void, src: *const c_void, n: size_t) -> *mut c_void;
-    pub fn memset(dest: *mut c_void, c: c_int, n: size_t) -> *mut c_void;
-}
-
-// These are all inline functions on android, so they end up just being entirely
-// missing on that platform.
-
-#[cfg(not(target_os = "android"))]
-extern "C" {
-    pub fn abs(i: c_int) -> c_int;
-    pub fn atof(s: *const c_char) -> c_double;
-    pub fn labs(i: c_long) -> c_long;
-    pub fn rand() -> c_int;
-    pub fn srand(seed: c_uint);
-}
diff --git a/src/redox/mod.rs b/src/redox/mod.rs
index 7c7f4229e6..9870fa6dca 100644
--- a/src/redox/mod.rs
+++ b/src/redox/mod.rs
@@ -1,3 +1,32 @@
+
+pub type int8_t = i8;
+pub type int16_t = i16;
+pub type int32_t = i32;
+pub type int64_t = i64;
+pub type uint8_t = u8;
+pub type uint16_t = u16;
+pub type uint32_t = u32;
+pub type uint64_t = u64;
+
+pub type c_schar = i8;
+pub type c_uchar = u8;
+pub type c_short = i16;
+pub type c_ushort = u16;
+pub type c_int = i32;
+pub type c_uint = u32;
+pub type c_float = f32;
+pub type c_double = f64;
+pub type c_longlong = i64;
+pub type c_ulonglong = u64;
+pub type intmax_t = i64;
+pub type uintmax_t = u64;
+
+pub type size_t = usize;
+pub type ptrdiff_t = isize;
+pub type intptr_t = isize;
+pub type uintptr_t = usize;
+pub type ssize_t = isize;
+
 pub type c_char = i8;
 pub type c_long = i64;
 pub type c_ulong = u64;
@@ -25,6 +54,9 @@ s! {
     }
 }
 
+pub const INT_MIN: c_int = -2147483648;
+pub const INT_MAX: c_int = 2147483647;
+
 pub const STDIN_FILENO: ::c_int = 0;
 pub const STDOUT_FILENO: ::c_int = 1;
 pub const STDERR_FILENO: ::c_int = 2;
@@ -117,7 +149,111 @@ pub const SIGIO:     ::c_int = 29;
 pub const SIGPWR:    ::c_int = 30;
 pub const SIGSYS:    ::c_int = 31;
 
+pub enum FILE {}
+pub enum fpos_t {} // TODO: fill this out with a struct
+
 extern {
+    pub fn isalnum(c: c_int) -> c_int;
+    pub fn isalpha(c: c_int) -> c_int;
+    pub fn iscntrl(c: c_int) -> c_int;
+    pub fn isdigit(c: c_int) -> c_int;
+    pub fn isgraph(c: c_int) -> c_int;
+    pub fn islower(c: c_int) -> c_int;
+    pub fn isprint(c: c_int) -> c_int;
+    pub fn ispunct(c: c_int) -> c_int;
+    pub fn isspace(c: c_int) -> c_int;
+    pub fn isupper(c: c_int) -> c_int;
+    pub fn isxdigit(c: c_int) -> c_int;
+    pub fn tolower(c: c_int) -> c_int;
+    pub fn toupper(c: c_int) -> c_int;
+    pub fn fopen(filename: *const c_char, mode: *const c_char) -> *mut FILE;
+    pub fn freopen(filename: *const c_char, mode: *const c_char,
+                   file: *mut FILE) -> *mut FILE;
+    pub fn fflush(file: *mut FILE) -> c_int;
+    pub fn fclose(file: *mut FILE) -> c_int;
+    pub fn remove(filename: *const c_char) -> c_int;
+    pub fn rename(oldname: *const c_char, newname: *const c_char) -> c_int;
+    pub fn tmpfile() -> *mut FILE;
+    pub fn setvbuf(stream: *mut FILE, buffer: *mut c_char, mode: c_int,
+                   size: size_t) -> c_int;
+    pub fn setbuf(stream: *mut FILE, buf: *mut c_char);
+    pub fn getchar() -> c_int;
+    pub fn putchar(c: c_int) -> c_int;
+    pub fn fgetc(stream: *mut FILE) -> c_int;
+    pub fn fgets(buf: *mut c_char, n: c_int, stream: *mut FILE) -> *mut c_char;
+    pub fn fputc(c: c_int, stream: *mut FILE) -> c_int;
+    pub fn fputs(s: *const c_char, stream: *mut FILE) -> c_int;
+    pub fn puts(s: *const c_char) -> c_int;
+    pub fn ungetc(c: c_int, stream: *mut FILE) -> c_int;
+    pub fn fread(ptr: *mut c_void, size: size_t, nobj: size_t,
+                 stream: *mut FILE) -> size_t;
+    pub fn fwrite(ptr: *const c_void, size: size_t, nobj: size_t,
+                  stream: *mut FILE) -> size_t;
+    pub fn fseek(stream: *mut FILE, offset: c_long, whence: c_int) -> c_int;
+    pub fn ftell(stream: *mut FILE) -> c_long;
+    pub fn rewind(stream: *mut FILE);
+    pub fn fgetpos(stream: *mut FILE, ptr: *mut fpos_t) -> c_int;
+    pub fn fsetpos(stream: *mut FILE, ptr: *const fpos_t) -> c_int;
+    pub fn feof(stream: *mut FILE) -> c_int;
+    pub fn ferror(stream: *mut FILE) -> c_int;
+    pub fn perror(s: *const c_char);
+    pub fn atoi(s: *const c_char) -> c_int;
+    pub fn strtod(s: *const c_char, endp: *mut *mut c_char) -> c_double;
+    pub fn strtol(s: *const c_char, endp: *mut *mut c_char,
+                  base: c_int) -> c_long;
+    pub fn strtoul(s: *const c_char, endp: *mut *mut c_char,
+                   base: c_int) -> c_ulong;
+    pub fn calloc(nobj: size_t, size: size_t) -> *mut c_void;
+    pub fn malloc(size: size_t) -> *mut c_void;
+    pub fn realloc(p: *mut c_void, size: size_t) -> *mut c_void;
+    pub fn free(p: *mut c_void);
+    pub fn abort() -> !;
+    pub fn exit(status: c_int) -> !;
+    pub fn _exit(status: c_int) -> !;
+    pub fn atexit(cb: extern fn()) -> c_int;
+    pub fn system(s: *const c_char) -> c_int;
+    pub fn getenv(s: *const c_char) -> *mut c_char;
+
+    pub fn strcpy(dst: *mut c_char, src: *const c_char) -> *mut c_char;
+    pub fn strncpy(dst: *mut c_char, src: *const c_char,
+                   n: size_t) -> *mut c_char;
+    pub fn strcat(s: *mut c_char, ct: *const c_char) -> *mut c_char;
+    pub fn strncat(s: *mut c_char, ct: *const c_char,
+                   n: size_t) -> *mut c_char;
+    pub fn strcmp(cs: *const c_char, ct: *const c_char) -> c_int;
+    pub fn strncmp(cs: *const c_char, ct: *const c_char,
+                   n: size_t) -> c_int;
+    pub fn strcoll(cs: *const c_char, ct: *const c_char) -> c_int;
+    pub fn strchr(cs: *const c_char, c: c_int) -> *mut c_char;
+    pub fn strrchr(cs: *const c_char, c: c_int) -> *mut c_char;
+    pub fn strspn(cs: *const c_char, ct: *const c_char) -> size_t;
+    pub fn strcspn(cs: *const c_char, ct: *const c_char) -> size_t;
+    pub fn strdup(cs: *const c_char) -> *mut c_char;
+    pub fn strpbrk(cs: *const c_char, ct: *const c_char) -> *mut c_char;
+    pub fn strstr(cs: *const c_char, ct: *const c_char) -> *mut c_char;
+    pub fn strlen(cs: *const c_char) -> size_t;
+    pub fn strnlen(cs: *const c_char, maxlen: size_t) -> size_t;
+    pub fn strerror(n: c_int) -> *mut c_char;
+    pub fn strtok(s: *mut c_char, t: *const c_char) -> *mut c_char;
+    pub fn strxfrm(s: *mut c_char, ct: *const c_char, n: size_t) -> size_t;
+    pub fn wcslen(buf: *const wchar_t) -> size_t;
+    pub fn wcstombs(dest: *mut c_char, src: *const wchar_t,
+                    n: size_t) -> ::size_t;
+
+    pub fn memchr(cx: *const c_void, c: c_int, n: size_t) -> *mut c_void;
+    pub fn memcmp(cx: *const c_void, ct: *const c_void, n: size_t) -> c_int;
+    pub fn memcpy(dest: *mut c_void, src: *const c_void,
+                  n: size_t) -> *mut c_void;
+    pub fn memmove(dest: *mut c_void, src: *const c_void,
+                   n: size_t) -> *mut c_void;
+    pub fn memset(dest: *mut c_void, c: c_int, n: size_t) -> *mut c_void;
+
+    pub fn abs(i: c_int) -> c_int;
+    pub fn atof(s: *const c_char) -> c_double;
+    pub fn labs(i: c_long) -> c_long;
+    pub fn rand() -> c_int;
+    pub fn srand(seed: c_uint);
+
     pub fn chown(path: *const c_char, uid: uid_t, gid: gid_t) -> ::c_int;
     pub fn close(fd: ::c_int) -> ::c_int;
     pub fn fchown(fd: ::c_int, uid: ::uid_t, gid: ::gid_t) -> ::c_int;
@@ -140,3 +276,21 @@ extern {}
 pub use self::net::*;
 
 mod net;
+
+cfg_if! {
+    if #[cfg(core_cvoid)] {
+        pub use core::ffi::c_void;
+    } else {
+        // Use repr(u8) as LLVM expects `void*` to be the same as `i8*` to help
+        // enable more optimization opportunities around it recognizing things
+        // like malloc/free.
+        #[repr(u8)]
+        pub enum c_void {
+            // Two dummy variants so the #[repr] attribute can be used.
+            #[doc(hidden)]
+            __variant1,
+            #[doc(hidden)]
+            __variant2,
+        }
+    }
+}
diff --git a/src/sgx.rs b/src/sgx.rs
index b95a91709f..045133399b 100644
--- a/src/sgx.rs
+++ b/src/sgx.rs
@@ -1,5 +1,54 @@
 //! SGX C types definition
 
+pub type int8_t = i8;
+pub type int16_t = i16;
+pub type int32_t = i32;
+pub type int64_t = i64;
+pub type uint8_t = u8;
+pub type uint16_t = u16;
+pub type uint32_t = u32;
+pub type uint64_t = u64;
+
+pub type c_schar = i8;
+pub type c_uchar = u8;
+pub type c_short = i16;
+pub type c_ushort = u16;
+pub type c_int = i32;
+pub type c_uint = u32;
+pub type c_float = f32;
+pub type c_double = f64;
+pub type c_longlong = i64;
+pub type c_ulonglong = u64;
+pub type intmax_t = i64;
+pub type uintmax_t = u64;
+
+pub type size_t = usize;
+pub type ptrdiff_t = isize;
+pub type intptr_t = isize;
+pub type uintptr_t = usize;
+pub type ssize_t = isize;
+
 pub type c_char = i8;
 pub type c_long = i64;
 pub type c_ulong = u64;
+
+pub const INT_MIN: c_int = -2147483648;
+pub const INT_MAX: c_int = 2147483647;
+
+cfg_if! {
+    if #[cfg(core_cvoid)] {
+        pub use core::ffi::c_void;
+    } else {
+        // Use repr(u8) as LLVM expects `void*` to be the same as `i8*` to help
+        // enable more optimization opportunities around it recognizing things
+        // like malloc/free.
+        #[repr(u8)]
+        pub enum c_void {
+            // Two dummy variants so the #[repr] attribute can be used.
+            #[doc(hidden)]
+            __variant1,
+            #[doc(hidden)]
+            __variant2,
+        }
+    }
+}
diff --git a/src/switch.rs b/src/switch.rs
index 240e938068..e2d9b491cb 100644
--- a/src/switch.rs
+++ b/src/switch.rs
@@ -1,7 +1,57 @@
 //! Switch C type definitions
 
+pub type int8_t = i8;
+pub type int16_t = i16;
+pub type int32_t = i32;
+pub type int64_t = i64;
+pub type uint8_t = u8;
+pub type uint16_t = u16;
+pub type uint32_t = u32;
+pub type uint64_t = u64;
+
+pub type c_schar = i8;
+pub type c_uchar = u8;
+pub type c_short = i16;
+pub type c_ushort = u16;
+pub type c_int = i32;
+pub type c_uint = u32;
+pub type c_float = f32;
+pub type c_double = f64;
+pub type c_longlong = i64;
+pub type c_ulonglong = u64;
+pub type intmax_t = i64;
+pub type uintmax_t = u64;
+
+pub type size_t = usize;
+pub type ptrdiff_t = isize;
+pub type intptr_t = isize;
+pub type uintptr_t = usize;
+pub type ssize_t = isize;
+
 pub type off_t = i64;
 pub type c_char = u8;
 pub type c_long = i64;
 pub type c_ulong = u64;
 pub type wchar_t = u32;
+
+pub const INT_MIN: c_int = -2147483648;
+pub const INT_MAX: c_int = 2147483647;
+
+cfg_if! {
+    if #[cfg(core_cvoid)] {
+        pub use core::ffi::c_void;
+    } else {
+        // Use repr(u8) as LLVM expects `void*` to be the same as `i8*` to help
+        // enable more optimization opportunities around it recognizing things
+        // like malloc/free.
+        #[repr(u8)]
+        pub enum c_void {
+            // Two dummy variants so the #[repr] attribute can be used.
+            #[doc(hidden)]
+            __variant1,
+            #[doc(hidden)]
+            __variant2,
+        }
+    }
+}
+
diff --git a/src/unix/bsd/mod.rs b/src/unix/bsd/mod.rs
index 05cf8fee4d..a2df23bf18 100644
--- a/src/unix/bsd/mod.rs
+++ b/src/unix/bsd/mod.rs
@@ -417,6 +417,12 @@ f! {
 }
 
 extern {
+    pub fn abs(i: ::c_int) -> ::c_int;
+    pub fn atof(s: *const ::c_char) -> ::c_double;
+    pub fn labs(i: ::c_long) -> ::c_long;
+    pub fn rand() -> ::c_int;
+    pub fn srand(seed: ::c_uint);
+
     pub fn getifaddrs(ifap: *mut *mut ::ifaddrs) -> ::c_int;
     pub fn freeifaddrs(ifa: *mut ::ifaddrs);
     pub fn setgroups(ngroups: ::c_int,
diff --git a/src/unix/haiku/mod.rs b/src/unix/haiku/mod.rs
index 307a5a40db..e65bca7f40 100644
--- a/src/unix/haiku/mod.rs
+++ b/src/unix/haiku/mod.rs
@@ -1086,6 +1086,14 @@ f! {
     }
 }
 
+extern {
+    pub fn abs(i: ::c_int) -> ::c_int;
+    pub fn atof(s: *const ::c_char) -> ::c_double;
+    pub fn labs(i: ::c_long) -> ::c_long;
+    pub fn rand() -> ::c_int;
+    pub fn srand(seed: ::c_uint);
+}
+
 #[link(name = "bsd")]
 extern {
     pub fn clock_gettime(clk_id: ::c_int, tp: *mut ::timespec) -> ::c_int;
diff --git a/src/unix/hermit/mod.rs b/src/unix/hermit/mod.rs
index bed6f7ae7f..aadfa1cf0f 100644
--- a/src/unix/hermit/mod.rs
+++ b/src/unix/hermit/mod.rs
@@ -696,6 +696,12 @@ f! {
 }
 
 extern {
+    pub fn abs(i: ::c_int) -> ::c_int;
+    pub fn atof(s: *const ::c_char) -> ::c_double;
+    pub fn labs(i: ::c_long) -> ::c_long;
+    pub fn rand() -> ::c_int;
+    pub fn srand(seed: ::c_uint);
+
     pub fn bind(s: ::c_int, name: *const ::sockaddr, namelen: ::socklen_t)
         -> ::c_int;
 
diff --git a/src/unix/mod.rs b/src/unix/mod.rs
index 06275a6994..2d25690b22 100644
--- a/src/unix/mod.rs
+++ b/src/unix/mod.rs
@@ -5,6 +5,34 @@
 
 use dox::Option;
 
+pub type int8_t = i8;
+pub type int16_t = i16;
+pub type int32_t = i32;
+pub type int64_t = i64;
+pub type uint8_t = u8;
+pub type uint16_t = u16;
+pub type uint32_t = u32;
+pub type uint64_t = u64;
+
+pub type c_schar = i8;
+pub type c_uchar = u8;
+pub type c_short = i16;
+pub type c_ushort = u16;
+pub type c_int = i32;
+pub type c_uint = u32;
+pub type c_float = f32;
+pub type c_double = f64;
+pub type c_longlong = i64;
+pub type c_ulonglong = u64;
+pub type intmax_t = i64;
+pub type uintmax_t = u64;
+
+pub type size_t = usize;
+pub type ptrdiff_t = isize;
+pub type intptr_t = isize;
+pub type uintptr_t = usize;
+pub type ssize_t = isize;
+
 pub type pid_t = i32;
 pub type uid_t = u32;
 pub type gid_t = u32;
@@ -188,6 +216,9 @@ s! {
     }
 }
 
+pub const INT_MIN: c_int = -2147483648;
+pub const INT_MAX: c_int = 2147483647;
+
 pub const SIG_DFL: sighandler_t = 0 as sighandler_t;
 pub const SIG_IGN: sighandler_t = 1 as sighandler_t;
 pub const SIG_ERR: sighandler_t = !0 as sighandler_t;
@@ -337,6 +368,135 @@ cfg_if! {
     }
 }
 
+pub enum FILE {}
+pub enum fpos_t {} // TODO: fill this out with a struct
+
+extern {
+    pub fn isalnum(c: c_int) -> c_int;
+    pub fn isalpha(c: c_int) -> c_int;
+    pub fn iscntrl(c: c_int) -> c_int;
+    pub fn isdigit(c: c_int) -> c_int;
+    pub fn isgraph(c: c_int) -> c_int;
+    pub fn islower(c: c_int) -> c_int;
+    pub fn isprint(c: c_int) -> c_int;
+    pub fn ispunct(c: c_int) -> c_int;
+    pub fn isspace(c: c_int) -> c_int;
+    pub fn isupper(c: c_int) -> c_int;
+    pub fn isxdigit(c: c_int) -> c_int;
+    pub fn tolower(c: c_int) -> c_int;
+    pub fn toupper(c: c_int) -> c_int;
+    #[cfg_attr(
+        all(target_os = "macos", target_arch = "x86"),
+        link_name = "fopen$UNIX2003"
+    )]
+    pub fn fopen(filename: *const c_char, mode: *const c_char) -> *mut FILE;
+    #[cfg_attr(
+        all(target_os = "macos", target_arch = "x86"),
+        link_name = "freopen$UNIX2003"
+    )]
+    pub fn freopen(filename: *const c_char, mode: *const c_char,
+                   file: *mut FILE) -> *mut FILE;
+    pub fn fflush(file: *mut FILE) -> c_int;
+    pub fn fclose(file: *mut FILE) -> c_int;
+    pub fn remove(filename: *const c_char) -> c_int;
+    pub fn rename(oldname: *const c_char, newname: *const c_char) -> c_int;
+    pub fn tmpfile() -> *mut FILE;
+    pub fn setvbuf(stream: *mut FILE, buffer: *mut c_char, mode: c_int,
+                   size: size_t) -> c_int;
+    pub fn setbuf(stream: *mut FILE, buf: *mut c_char);
+    pub fn getchar() -> c_int;
+    pub fn putchar(c: c_int) -> c_int;
+    pub fn fgetc(stream: *mut FILE) -> c_int;
+    pub fn fgets(buf: *mut c_char, n: c_int, stream: *mut FILE) -> *mut c_char;
+    pub fn fputc(c: c_int, stream: *mut FILE) -> c_int;
+    #[cfg_attr(
+        all(target_os = "macos", target_arch = "x86"),
+        link_name = "fputs$UNIX2003"
+    )]
+    pub fn fputs(s: *const c_char, stream: *mut FILE) -> c_int;
+    pub fn puts(s: *const c_char) -> c_int;
+    pub fn ungetc(c: c_int, stream: *mut FILE) -> c_int;
+    pub fn fread(ptr: *mut c_void, size: size_t, nobj: size_t,
+                 stream: *mut FILE) -> size_t;
+    #[cfg_attr(
+        all(target_os = "macos", target_arch = "x86"),
+        link_name = "fwrite$UNIX2003"
+    )]
+    pub fn fwrite(ptr: *const c_void, size: size_t, nobj: size_t,
+                  stream: *mut FILE) -> size_t;
+    pub fn fseek(stream: *mut FILE, offset: c_long, whence: c_int) -> c_int;
+    pub fn ftell(stream: *mut FILE) -> c_long;
+    pub fn rewind(stream: *mut FILE);
+    #[cfg_attr(target_os = "netbsd", link_name = "__fgetpos50")]
+    pub fn fgetpos(stream: *mut FILE, ptr: *mut fpos_t) -> c_int;
+    #[cfg_attr(target_os = "netbsd", link_name = "__fsetpos50")]
+    pub fn fsetpos(stream: *mut FILE, ptr: *const fpos_t) -> c_int;
+    pub fn feof(stream: *mut FILE) -> c_int;
+    pub fn ferror(stream: *mut FILE) -> c_int;
+    pub fn perror(s: *const c_char);
+    pub fn atoi(s: *const c_char) -> c_int;
+    #[cfg_attr(
+        all(target_os = "macos", target_arch = "x86"),
+        link_name = "strtod$UNIX2003"
+    )]
+    pub fn strtod(s: *const c_char, endp: *mut *mut c_char) -> c_double;
+    pub fn strtol(s: *const c_char, endp: *mut *mut c_char,
+                  base: c_int) -> c_long;
+    pub fn strtoul(s: *const c_char, endp: *mut *mut c_char,
+                   base: c_int) -> c_ulong;
+    pub fn calloc(nobj: size_t, size: size_t) -> *mut c_void;
+    pub fn malloc(size: size_t) -> *mut c_void;
+    pub fn realloc(p: *mut c_void, size: size_t) -> *mut c_void;
+    pub fn free(p: *mut c_void);
+    pub fn abort() -> !;
+    pub fn exit(status: c_int) -> !;
+    pub fn _exit(status: c_int) -> !;
+    pub fn atexit(cb: extern fn()) -> c_int;
+    #[cfg_attr(
+        all(target_os = "macos", target_arch = "x86"),
+        link_name = "system$UNIX2003"
+    )]
+    pub fn system(s: *const c_char) -> c_int;
+    pub fn getenv(s: *const c_char) -> *mut c_char;
+
+    pub fn strcpy(dst: *mut c_char, src: *const c_char) -> *mut c_char;
+    pub fn strncpy(dst: *mut c_char, src: *const c_char,
+                   n: size_t) -> *mut c_char;
+    pub fn strcat(s: *mut c_char, ct: *const c_char) -> *mut c_char;
+    pub fn strncat(s: *mut c_char, ct: *const c_char,
+                   n: size_t) -> *mut c_char;
+    pub fn strcmp(cs: *const c_char, ct: *const c_char) -> c_int;
+    pub fn strncmp(cs: *const c_char, ct: *const c_char, n: size_t) -> c_int;
+    pub fn strcoll(cs: *const c_char, ct: *const c_char) -> c_int;
+    pub fn strchr(cs: *const c_char, c: c_int) -> *mut c_char;
+    pub fn strrchr(cs: *const c_char, c: c_int) -> *mut c_char;
+    pub fn strspn(cs: *const c_char, ct: *const c_char) -> size_t;
+    pub fn strcspn(cs: *const c_char, ct: *const c_char) -> size_t;
+    pub fn strdup(cs: *const c_char) -> *mut c_char;
+    pub fn strpbrk(cs: *const c_char, ct: *const c_char) -> *mut c_char;
+    pub fn strstr(cs: *const c_char, ct: *const c_char) -> *mut c_char;
+    pub fn strlen(cs: *const c_char) -> size_t;
+    pub fn strnlen(cs: *const c_char, maxlen: size_t) -> size_t;
+    #[cfg_attr(
+        all(target_os = "macos", target_arch = "x86"),
+        link_name = "strerror$UNIX2003"
+    )]
+    pub fn strerror(n: c_int) -> *mut c_char;
+    pub fn strtok(s: *mut c_char, t: *const c_char) -> *mut c_char;
+    pub fn strxfrm(s: *mut c_char, ct: *const c_char, n: size_t) -> size_t;
+    pub fn wcslen(buf: *const wchar_t) -> size_t;
+    pub fn wcstombs(dest: *mut c_char, src: *const wchar_t,
+                    n: size_t) -> ::size_t;
+
+    pub fn memchr(cx: *const c_void, c: c_int, n: size_t) -> *mut c_void;
+    pub fn memcmp(cx: *const c_void, ct: *const c_void, n: size_t) -> c_int;
+    pub fn memcpy(dest: *mut c_void, src: *const c_void,
+                  n: size_t) -> *mut c_void;
+    pub fn memmove(dest: *mut c_void, src: *const c_void,
+                   n: size_t) -> *mut c_void;
+    pub fn memset(dest: *mut c_void, c: c_int, n: size_t) -> *mut c_void;
+}
+
 extern {
     #[cfg_attr(target_os = "netbsd", link_name = "__getpwnam50")]
     pub fn getpwnam(name: *const ::c_char) -> *mut passwd;
@@ -984,3 +1144,21 @@ cfg_if! {
         // Unknown target_os
     }
 }
+
+cfg_if! {
+    if #[cfg(core_cvoid)] {
+        pub use core::ffi::c_void;
+    } else {
+        // Use repr(u8) as LLVM expects `void*` to be the same as `i8*` to help
+        // enable more optimization opportunities around it recognizing things
+        // like malloc/free.
+        #[repr(u8)]
+        pub enum c_void {
+            // Two dummy variants so the #[repr] attribute can be used.
+            #[doc(hidden)]
+            __variant1,
+            #[doc(hidden)]
+            __variant2,
+        }
+    }
+}
diff --git a/src/unix/newlib/mod.rs b/src/unix/newlib/mod.rs
index 9968d36685..77a4eb9901 100644
--- a/src/unix/newlib/mod.rs
+++ b/src/unix/newlib/mod.rs
@@ -654,6 +654,12 @@ f! {
 }
 
 extern {
+    pub fn abs(i: ::c_int) -> ::c_int;
+    pub fn atof(s: *const ::c_char) -> ::c_double;
+    pub fn labs(i: ::c_long) -> ::c_long;
+    pub fn rand() -> ::c_int;
+    pub fn srand(seed: ::c_uint);
+
     pub fn bind(fd: ::c_int, addr: *const sockaddr, len: socklen_t) -> ::c_int;
     pub fn closesocket(sockfd: ::c_int) -> ::c_int;
     pub fn ioctl(fd: ::c_int, request: ::c_ulong, ...) -> ::c_int;
diff --git a/src/unix/notbsd/emscripten.rs b/src/unix/notbsd/emscripten.rs
index e680032cc7..28791d8fd5 100644
--- a/src/unix/notbsd/emscripten.rs
+++ b/src/unix/notbsd/emscripten.rs
@@ -1573,6 +1573,12 @@ f! {
 }
 
 extern {
+    pub fn abs(i: ::c_int) -> ::c_int;
+    pub fn atof(s: *const ::c_char) -> ::c_double;
+    pub fn labs(i: ::c_long) -> ::c_long;
+    pub fn rand() -> ::c_int;
+    pub fn srand(seed: ::c_uint);
+
     pub fn setpwent();
     pub fn endpwent();
     pub fn getpwent() -> *mut passwd;
diff --git a/src/unix/notbsd/linux/mod.rs b/src/unix/notbsd/linux/mod.rs
index a47e809c24..78dced152d 100644
--- a/src/unix/notbsd/linux/mod.rs
+++ b/src/unix/notbsd/linux/mod.rs
@@ -1754,6 +1754,12 @@ f! {
 }
 
 extern {
+    pub fn abs(i: ::c_int) -> ::c_int;
+    pub fn atof(s: *const ::c_char) -> ::c_double;
+    pub fn labs(i: ::c_long) -> ::c_long;
+    pub fn rand() -> ::c_int;
+    pub fn srand(seed: ::c_uint);
+
     pub fn aio_read(aiocbp: *mut aiocb) -> ::c_int;
     pub fn aio_write(aiocbp: *mut aiocb) -> ::c_int;
     pub fn aio_fsync(op: ::c_int, aiocbp: *mut aiocb) -> ::c_int;
diff --git a/src/unix/solaris/mod.rs b/src/unix/solaris/mod.rs
index 0df424ddf2..c4ec111b42 100644
--- a/src/unix/solaris/mod.rs
+++ b/src/unix/solaris/mod.rs
@@ -1258,6 +1258,12 @@ f! {
 }
 
 extern {
+    pub fn abs(i: ::c_int) -> ::c_int;
+    pub fn atof(s: *const ::c_char) -> ::c_double;
+    pub fn labs(i: ::c_long) -> ::c_long;
+    pub fn rand() -> ::c_int;
+    pub fn srand(seed: ::c_uint);
+
     pub fn getifaddrs(ifap: *mut *mut ::ifaddrs) -> ::c_int;
     pub fn freeifaddrs(ifa: *mut ::ifaddrs);
 
diff --git a/src/unix/uclibc/mod.rs b/src/unix/uclibc/mod.rs
index 03a8594f4f..2c80fd190d 100644
--- a/src/unix/uclibc/mod.rs
+++ b/src/unix/uclibc/mod.rs
@@ -1551,6 +1551,12 @@ f! {
 }
 
 extern {
+    pub fn abs(i: ::c_int) -> ::c_int;
+    pub fn atof(s: *const ::c_char) -> ::c_double;
+    pub fn labs(i: ::c_long) -> ::c_long;
+    pub fn rand() -> ::c_int;
+    pub fn srand(seed: ::c_uint);
+
     pub fn fdatasync(fd: ::c_int) -> ::c_int;
     pub fn mincore(addr: *mut ::c_void, len: ::size_t,
                    vec: *mut ::c_uchar) -> ::c_int;
diff --git a/src/windows.rs b/src/windows.rs
index bdb0e02f1b..4fc2c16a61 100644
--- a/src/windows.rs
+++ b/src/windows.rs
@@ -1,5 +1,33 @@
 //! Windows CRT definitions
 
+pub type int8_t = i8;
+pub type int16_t = i16;
+pub type int32_t = i32;
+pub type int64_t = i64;
+pub type uint8_t = u8;
+pub type uint16_t = u16;
+pub type uint32_t = u32;
+pub type uint64_t = u64;
+
+pub type c_schar = i8;
+pub type c_uchar = u8;
+pub type c_short = i16;
+pub type c_ushort = u16;
+pub type c_int = i32;
+pub type c_uint = u32;
+pub type c_float = f32;
+pub type c_double = f64;
+pub type c_longlong = i64;
+pub type c_ulonglong = u64;
+pub type intmax_t = i64;
+pub type uintmax_t = u64;
+
+pub type size_t = usize;
+pub type ptrdiff_t = isize;
+pub type intptr_t = isize;
+pub type uintptr_t = usize;
+pub type ssize_t = isize;
+
 pub type c_char = i8;
 pub type c_long = i32;
 pub type c_ulong = u32;
@@ -66,6 +94,9 @@ s! {
     }
 }
 
+pub const INT_MIN: c_int = -2147483648;
+pub const INT_MAX: c_int = 2147483647;
+
 pub const EXIT_FAILURE: ::c_int = 1;
 pub const EXIT_SUCCESS: ::c_int = 0;
 pub const RAND_MAX: ::c_int = 32767;
@@ -164,7 +195,110 @@ pub const STRUNCATE: ::c_int = 80;
 #[link(name = "libcmt", cfg(target_feature = "crt-static"))]
 extern {}
 
+pub enum FILE {}
+pub enum fpos_t {} // TODO: fill this out with a struct
+
 extern {
+    pub fn isalnum(c: c_int) -> c_int;
+    pub fn isalpha(c: c_int) -> c_int;
+    pub fn iscntrl(c: c_int) -> c_int;
+    pub fn isdigit(c: c_int) -> c_int;
+    pub fn isgraph(c: c_int) -> c_int;
+    pub fn islower(c: c_int) -> c_int;
+    pub fn isprint(c: c_int) -> c_int;
+    pub fn ispunct(c: c_int) -> c_int;
+    pub fn isspace(c: c_int) -> c_int;
+    pub fn isupper(c: c_int) -> c_int;
+    pub fn isxdigit(c: c_int) -> c_int;
+    pub fn tolower(c: c_int) -> c_int;
+    pub fn toupper(c: c_int) -> c_int;
+    pub fn fopen(filename: *const c_char, mode: *const c_char) -> *mut FILE;
+    pub fn freopen(filename: *const c_char, mode: *const c_char,
+                   file: *mut FILE) -> *mut FILE;
+    pub fn fflush(file: *mut FILE) -> c_int;
+    pub fn fclose(file: *mut FILE) -> c_int;
+    pub fn remove(filename: *const c_char) -> c_int;
+    pub fn rename(oldname: *const c_char, newname: *const c_char) -> c_int;
+    pub fn tmpfile() -> *mut FILE;
+    pub fn setvbuf(stream: *mut FILE, buffer: *mut c_char, mode: c_int,
+                   size: size_t) -> c_int;
+    pub fn setbuf(stream: *mut FILE, buf: *mut c_char);
+    pub fn getchar() -> c_int;
+    pub fn putchar(c: c_int) -> c_int;
+    pub fn fgetc(stream: *mut FILE) -> c_int;
+    pub fn fgets(buf: *mut c_char, n: c_int, stream: *mut FILE) -> *mut c_char;
+    pub fn fputc(c: c_int, stream: *mut FILE) -> c_int;
+    pub fn fputs(s: *const c_char, stream: *mut FILE) -> c_int;
+    pub fn puts(s: *const c_char) -> c_int;
+    pub fn ungetc(c: c_int, stream: *mut FILE) -> c_int;
+    pub fn fread(ptr: *mut c_void, size: size_t, nobj: size_t,
+                 stream: *mut FILE) -> size_t;
+    pub fn fwrite(ptr: *const c_void, size: size_t, nobj: size_t,
+                  stream: *mut FILE) -> size_t;
+    pub fn fseek(stream: *mut FILE, offset: c_long, whence: c_int) -> c_int;
+    pub fn ftell(stream: *mut FILE) -> c_long;
+    pub fn rewind(stream: *mut FILE);
+    pub fn fgetpos(stream: *mut FILE, ptr: *mut fpos_t) -> c_int;
+    pub fn fsetpos(stream: *mut FILE, ptr: *const fpos_t) -> c_int;
+    pub fn feof(stream: *mut FILE) -> c_int;
+    pub fn ferror(stream: *mut FILE) -> c_int;
+    pub fn perror(s: *const c_char);
+    pub fn atoi(s: *const c_char) -> c_int;
+    pub fn strtod(s: *const c_char, endp: *mut *mut c_char) -> c_double;
+    pub fn strtol(s: *const c_char, endp: *mut *mut c_char,
+                  base: c_int) -> c_long;
+    pub fn strtoul(s: *const c_char, endp: *mut *mut c_char,
+                   base: c_int) -> c_ulong;
+    pub fn calloc(nobj: size_t, size: size_t) -> *mut c_void;
+    pub fn malloc(size: size_t) -> *mut c_void;
+    pub fn realloc(p: *mut c_void, size: size_t) -> *mut c_void;
+    pub fn free(p: *mut c_void);
+    pub fn abort() -> !;
+    pub fn exit(status: c_int) -> !;
+    pub fn _exit(status: c_int) -> !;
+    pub fn atexit(cb: extern fn()) -> c_int;
+    pub fn system(s: *const c_char) -> c_int;
+    pub fn getenv(s: *const c_char) -> *mut c_char;
+
+    pub fn strcpy(dst: *mut c_char, src: *const c_char) -> *mut c_char;
+    pub fn strncpy(dst: *mut c_char, src: *const c_char,
+                   n: size_t) -> *mut c_char;
+    pub fn strcat(s: *mut c_char, ct: *const c_char) -> *mut c_char;
+    pub fn strncat(s: *mut c_char, ct: *const c_char,
+                   n: size_t) -> *mut c_char;
+    pub fn strcmp(cs: *const c_char, ct: *const c_char) -> c_int;
+    pub fn strncmp(cs: *const c_char, ct: *const c_char, n: size_t) -> c_int;
+    pub fn strcoll(cs: *const c_char, ct: *const c_char) -> c_int;
+    pub fn strchr(cs: *const c_char, c: c_int) -> *mut c_char;
+    pub fn strrchr(cs: *const c_char, c: c_int) -> *mut c_char;
+    pub fn strspn(cs: *const c_char, ct: *const c_char) -> size_t;
+    pub fn strcspn(cs: *const c_char, ct: *const c_char) -> size_t;
+    pub fn strdup(cs: *const c_char) -> *mut c_char;
+    pub fn strpbrk(cs: *const c_char, ct: *const c_char) -> *mut c_char;
+    pub fn strstr(cs: *const c_char, ct: *const c_char) -> *mut c_char;
+    pub fn strlen(cs: *const c_char) -> size_t;
+    pub fn strnlen(cs: *const c_char, maxlen: size_t) -> size_t;
+    pub fn strerror(n: c_int) -> *mut c_char;
+    pub fn strtok(s: *mut c_char, t: *const c_char) -> *mut c_char;
+    pub fn strxfrm(s: *mut c_char, ct: *const c_char, n: size_t) -> size_t;
+    pub fn wcslen(buf: *const wchar_t) -> size_t;
+    pub fn wcstombs(dest: *mut c_char, src: *const wchar_t,
+                    n: size_t) -> ::size_t;
+
+    pub fn memchr(cx: *const c_void, c: c_int, n: size_t) -> *mut c_void;
+    pub fn memcmp(cx: *const c_void, ct: *const c_void, n: size_t) -> c_int;
+    pub fn memcpy(dest: *mut c_void, src: *const c_void,
+                  n: size_t) -> *mut c_void;
+    pub fn memmove(dest: *mut c_void, src: *const c_void,
+                   n: size_t) -> *mut c_void;
+    pub fn memset(dest: *mut c_void, c: c_int, n: size_t) -> *mut c_void;
+
+    pub fn abs(i: c_int) -> c_int;
+    pub fn atof(s: *const c_char) -> c_double;
+    pub fn labs(i: c_long) -> c_long;
+    pub fn rand() -> c_int;
+    pub fn srand(seed: c_uint);
+
     #[link_name = "_chmod"]
     pub fn chmod(path: *const c_char, mode: ::c_int) -> ::c_int;
     #[link_name = "_wchmod"]
@@ -246,3 +380,21 @@ extern {
     pub fn wsetlocale(category: ::c_int,
                       locale: *const wchar_t) -> *mut wchar_t;
 }
+
+cfg_if! {
+    if #[cfg(core_cvoid)] {
+        pub use core::ffi::c_void;
+    } else {
+        // Use repr(u8) as LLVM expects `void*` to be the same as `i8*` to help
+        // enable more optimization opportunities around it recognizing things
+        // like malloc/free.
+        #[repr(u8)]
+        pub enum c_void {
+            // Two dummy variants so the #[repr] attribute can be used.
+            #[doc(hidden)]
+            __variant1,
+            #[doc(hidden)]
+            __variant2,
+        }
+    }
+}