Constify C constructors and flags tables (#12223)

22 files changed, 32 insertions, 27 deletions

diff --git a/Changes b/Changes
index 75c07f1984..a860b9e1b7 100644
--- a/Changes
+++ b/Changes
@@ -10,6 +10,10 @@ Working version
   of `caml_read_directory`.  Also, check for overflows in ext table sizes.
   (Xavier Leroy, report by Arseniy Alekseyev, review by Gabriel Scherer)
 
+- #12223: Constify constructors and flags tables in C code. Now these
+  tables will go in the readonly segment, where they belong.
+  (Antonin Décimo, review by Gabriel Scherer and Xavier Leroy)
+
 ### Code generation and optimizations:
 
 ### Standard library:
diff --git a/otherlibs/unix/access.c b/otherlibs/unix/access.c
index 0f7b3b3daf..48d95f7acb 100644
--- a/otherlibs/unix/access.c
+++ b/otherlibs/unix/access.c
@@ -35,7 +35,7 @@
 # endif
 #endif
 
-static int access_permission_table[] = {
+static const int access_permission_table[] = {
   R_OK,
   W_OK,
 #ifdef _WIN32
diff --git a/otherlibs/unix/cst2constr.c b/otherlibs/unix/cst2constr.c
index eab427e0b2..7bade04709 100644
--- a/otherlibs/unix/cst2constr.c
+++ b/otherlibs/unix/cst2constr.c
@@ -17,7 +17,7 @@
 #include <caml/fail.h>
 #include "cst2constr.h"
 
-value caml_unix_cst_to_constr(int n, int *tbl, int size, int deflt)
+value caml_unix_cst_to_constr(int n, const int *tbl, int size, int deflt)
 {
   int i;
   for (i = 0; i < size; i++)
diff --git a/otherlibs/unix/cst2constr.h b/otherlibs/unix/cst2constr.h
index 075b6d4d2a..324d617f50 100644
--- a/otherlibs/unix/cst2constr.h
+++ b/otherlibs/unix/cst2constr.h
@@ -13,4 +13,5 @@
 /*                                                                        */
 /**************************************************************************/
 
-extern value caml_unix_cst_to_constr(int n, int * tbl, int size, int deflt);
+extern value caml_unix_cst_to_constr(int n, const int * tbl, int size,
+                                     int deflt);
diff --git a/otherlibs/unix/getnameinfo.c b/otherlibs/unix/getnameinfo.c
index bc7be72463..304c2576e2 100644
--- a/otherlibs/unix/getnameinfo.c
+++ b/otherlibs/unix/getnameinfo.c
@@ -29,7 +29,7 @@
 #include <netdb.h>
 #endif
 
-static int getnameinfo_flag_table[] = {
+static const int getnameinfo_flag_table[] = {
   NI_NOFQDN, NI_NUMERICHOST, NI_NAMEREQD, NI_NUMERICSERV, NI_DGRAM
 };
 
diff --git a/otherlibs/unix/lockf_unix.c b/otherlibs/unix/lockf_unix.c
index 43796c71a2..371e26fad2 100644
--- a/otherlibs/unix/lockf_unix.c
+++ b/otherlibs/unix/lockf_unix.c
@@ -96,7 +96,7 @@ CAMLprim value caml_unix_lockf(value fd, value cmd, value span)
 #define F_TEST 3
 #endif
 
-static int lock_command_table[] = {
+static const int lock_command_table[] = {
   F_ULOCK, F_LOCK, F_TLOCK, F_TEST, F_LOCK, F_TLOCK
 };
 
diff --git a/otherlibs/unix/lseek_unix.c b/otherlibs/unix/lseek_unix.c
index 2264c3b969..99f2fccbd8 100644
--- a/otherlibs/unix/lseek_unix.c
+++ b/otherlibs/unix/lseek_unix.c
@@ -35,7 +35,7 @@
 #define EOVERFLOW ERANGE
 #endif
 
-static int seek_command_table[] = {
+static const int seek_command_table[] = {
   SEEK_SET, SEEK_CUR, SEEK_END
 };
 
diff --git a/otherlibs/unix/open_unix.c b/otherlibs/unix/open_unix.c
index b527d8907e..41a566395a 100644
--- a/otherlibs/unix/open_unix.c
+++ b/otherlibs/unix/open_unix.c
@@ -38,7 +38,7 @@
 #define O_RSYNC 0
 #endif
 
-static int open_flag_table[15] = {
+static const int open_flag_table[15] = {
   O_RDONLY, O_WRONLY, O_RDWR, O_NONBLOCK, O_APPEND, O_CREAT, O_TRUNC, O_EXCL,
   O_NOCTTY, O_DSYNC, O_SYNC, O_RSYNC,
   0, /* O_SHARE_DELETE, Windows-only */
@@ -48,7 +48,7 @@ static int open_flag_table[15] = {
 
 enum { CLOEXEC = 1, KEEPEXEC = 2 };
 
-static int open_cloexec_table[15] = {
+static const int open_cloexec_table[15] = {
   0, 0, 0, 0, 0, 0, 0, 0,
   0, 0, 0, 0,
   0,
diff --git a/otherlibs/unix/open_win32.c b/otherlibs/unix/open_win32.c
index b4e02aefe9..6d545769f7 100644
--- a/otherlibs/unix/open_win32.c
+++ b/otherlibs/unix/open_win32.c
@@ -22,22 +22,22 @@
 #include "unixsupport.h"
 #include <fcntl.h>
 
-static int open_access_flags[15] = {
+static const int open_access_flags[15] = {
   GENERIC_READ, GENERIC_WRITE, GENERIC_READ|GENERIC_WRITE,
   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
 };
 
-static int open_create_flags[15] = {
+static const int open_create_flags[15] = {
   0, 0, 0, 0, 0, O_CREAT, O_TRUNC, O_EXCL, 0, 0, 0, 0, 0, 0, 0
 };
 
-static int open_share_flags[15] = {
+static const int open_share_flags[15] = {
   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, FILE_SHARE_DELETE, 0, 0
 };
 
 enum { CLOEXEC = 1, KEEPEXEC = 2 };
 
-static int open_cloexec_flags[15] = {
+static const int open_cloexec_flags[15] = {
   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, CLOEXEC, KEEPEXEC
 };
 
diff --git a/otherlibs/unix/sendrecv_unix.c b/otherlibs/unix/sendrecv_unix.c
index 5ed785816c..46122888aa 100644
--- a/otherlibs/unix/sendrecv_unix.c
+++ b/otherlibs/unix/sendrecv_unix.c
@@ -24,7 +24,7 @@
 #ifdef HAS_SOCKETS
 #include "socketaddr.h"
 
-static int msg_flag_table[] = {
+static const int msg_flag_table[] = {
   MSG_OOB, MSG_DONTROUTE, MSG_PEEK
 };
 
diff --git a/otherlibs/unix/sendrecv_win32.c b/otherlibs/unix/sendrecv_win32.c
index 699babd9ca..1fc41d7098 100644
--- a/otherlibs/unix/sendrecv_win32.c
+++ b/otherlibs/unix/sendrecv_win32.c
@@ -20,7 +20,7 @@
 #include "unixsupport.h"
 #include "socketaddr.h"
 
-static int msg_flag_table[] = {
+static const int msg_flag_table[] = {
   MSG_OOB, MSG_DONTROUTE, MSG_PEEK
 };
 
diff --git a/otherlibs/unix/shutdown_unix.c b/otherlibs/unix/shutdown_unix.c
index 8c750e2479..898eebbb2d 100644
--- a/otherlibs/unix/shutdown_unix.c
+++ b/otherlibs/unix/shutdown_unix.c
@@ -21,7 +21,7 @@
 
 #include <sys/socket.h>
 
-static int shutdown_command_table[] = {
+static const int shutdown_command_table[] = {
   0, 1, 2
 };
 
diff --git a/otherlibs/unix/shutdown_win32.c b/otherlibs/unix/shutdown_win32.c
index a5f1d8c011..9bb0b3ed6b 100644
--- a/otherlibs/unix/shutdown_win32.c
+++ b/otherlibs/unix/shutdown_win32.c
@@ -16,7 +16,7 @@
 #include <caml/mlvalues.h>
 #include "unixsupport.h"
 
-static int shutdown_command_table[] = {
+static const int shutdown_command_table[] = {
   0, 1, 2
 };
 
diff --git a/otherlibs/unix/stat_unix.c b/otherlibs/unix/stat_unix.c
index 31b166fc65..3b28ef8409 100644
--- a/otherlibs/unix/stat_unix.c
+++ b/otherlibs/unix/stat_unix.c
@@ -44,7 +44,7 @@
 #define EOVERFLOW ERANGE
 #endif
 
-static int file_kind_table[] = {
+static const int file_kind_table[] = {
   S_IFREG, S_IFDIR, S_IFCHR, S_IFBLK, S_IFLNK, S_IFIFO, S_IFSOCK
 };
 
diff --git a/otherlibs/unix/stat_win32.c b/otherlibs/unix/stat_win32.c
index 197e4340d6..7f7b17e708 100644
--- a/otherlibs/unix/stat_win32.c
+++ b/otherlibs/unix/stat_win32.c
@@ -59,7 +59,7 @@
 #define S_IFBLK 0
 #endif
 
-static int file_kind_table[] = {
+static const int file_kind_table[] = {
   S_IFREG, S_IFDIR, S_IFCHR, S_IFBLK, S_IFLNK, S_IFIFO, S_IFSOCK
 };
 
diff --git a/otherlibs/unix/termios.c b/otherlibs/unix/termios.c
index f41af150c7..b92ae42661 100644
--- a/otherlibs/unix/termios.c
+++ b/otherlibs/unix/termios.c
@@ -307,7 +307,7 @@ CAMLprim value caml_unix_tcgetattr(value fd)
   return res;
 }
 
-static int when_flag_table[] = {
+static const int when_flag_table[] = {
   TCSANOW, TCSADRAIN, TCSAFLUSH
 };
 
@@ -346,7 +346,7 @@ CAMLprim value caml_unix_tcdrain(value fd)
 }
 #endif
 
-static int queue_flag_table[] = {
+static const int queue_flag_table[] = {
   TCIFLUSH, TCOFLUSH, TCIOFLUSH
 };
 
@@ -357,7 +357,7 @@ CAMLprim value caml_unix_tcflush(value fd, value queue)
   return Val_unit;
 }
 
-static int action_flag_table[] = {
+static const int action_flag_table[] = {
   TCOOFF, TCOON, TCIOFF, TCION
 };
 
diff --git a/otherlibs/unix/unixsupport_unix.c b/otherlibs/unix/unixsupport_unix.c
index 449af8b5c2..0d50e246b2 100644
--- a/otherlibs/unix/unixsupport_unix.c
+++ b/otherlibs/unix/unixsupport_unix.c
@@ -242,7 +242,7 @@
 #define EOVERFLOW (-1)
 #endif
 
-static int error_table[] = {
+static const int error_table[] = {
   E2BIG, EACCES, EAGAIN, EBADF, EBUSY, ECHILD, EDEADLK, EDOM,
   EEXIST, EFAULT, EFBIG, EINTR, EINVAL, EIO, EISDIR, EMFILE, EMLINK,
   ENAMETOOLONG, ENFILE, ENODEV, ENOENT, ENOEXEC, ENOLCK, ENOMEM, ENOSPC,
diff --git a/otherlibs/unix/unixsupport_win32.c b/otherlibs/unix/unixsupport_win32.c
index cb5eb35df7..509afa3ea3 100644
--- a/otherlibs/unix/unixsupport_win32.c
+++ b/otherlibs/unix/unixsupport_win32.c
@@ -251,7 +251,7 @@ void caml_win32_maperr(DWORD errcode)
 #undef EACCESS
 #define EACCESS EACCES
 
-static int error_table[] = {
+static const int error_table[] = {
   E2BIG, EACCESS, EAGAIN, EBADF, EBUSY, ECHILD, EDEADLK, EDOM,
   EEXIST, EFAULT, EFBIG, EINTR, EINVAL, EIO, EISDIR, EMFILE, EMLINK,
   ENAMETOOLONG, ENFILE, ENODEV, ENOENT, ENOEXEC, ENOLCK, ENOMEM, ENOSPC,
diff --git a/otherlibs/unix/wait.c b/otherlibs/unix/wait.c
index 3509c76b98..b5aa0516bd 100644
--- a/otherlibs/unix/wait.c
+++ b/otherlibs/unix/wait.c
@@ -83,7 +83,7 @@ CAMLprim value caml_unix_wait(value unit)
 #define waitpid(pid,status,opts) wait4(pid,status,opts,NULL)
 #endif
 
-static int wait_flag_table[] = {
+static const int wait_flag_table[] = {
   WNOHANG, WUNTRACED
 };
 
diff --git a/otherlibs/unix/winwait.c b/otherlibs/unix/winwait.c
index 2d28117af4..69ac8dd668 100644
--- a/otherlibs/unix/winwait.c
+++ b/otherlibs/unix/winwait.c
@@ -36,7 +36,7 @@ static value alloc_process_status(HANDLE pid, int status)
 
 enum { CAML_WNOHANG = 1, CAML_WUNTRACED = 2 };
 
-static int wait_flag_table[] = { CAML_WNOHANG, CAML_WUNTRACED };
+static const int wait_flag_table[] = { CAML_WNOHANG, CAML_WUNTRACED };
 
 CAMLprim value caml_unix_waitpid(value vflags, value vpid_req)
 {
diff --git a/runtime/extern.c b/runtime/extern.c
index 4301c3df13..7b5b81379b 100644
--- a/runtime/extern.c
+++ b/runtime/extern.c
@@ -991,7 +991,7 @@ oom1:
 
 #endif
 
-static int extern_flag_values[] = {
+static const int extern_flag_values[] = {
   NO_SHARING, CLOSURES, COMPAT_32, COMPRESSED
 };
 
diff --git a/runtime/signals.c b/runtime/signals.c
index 5a21024ad4..8abdf346b1 100644
--- a/runtime/signals.c
+++ b/runtime/signals.c
@@ -445,7 +445,7 @@ CAMLexport void caml_process_pending_actions(void)
 #define SIGXFSZ -1
 #endif
 
-static int posix_signals[] = {
+static const int posix_signals[] = {
   SIGABRT, SIGALRM, SIGFPE, SIGHUP, SIGILL, SIGINT, SIGKILL, SIGPIPE,
   SIGQUIT, SIGSEGV, SIGTERM, SIGUSR1, SIGUSR2, SIGCHLD, SIGCONT,
   SIGSTOP, SIGTSTP, SIGTTIN, SIGTTOU, SIGVTALRM, SIGPROF, SIGBUS,