Presume ISO C90 headers are always available

This includes <assert.h>, <ctype.h>, <errno.h>, <float.h>, <iso646.h>,
<limits.h>, <locale.h>, <math.h>, <setjmp.h>, <signal.h>, <stdarg.h>,
<stddef.h>, <stdio.h>, <stdlib.h>, <string.h>, <time.h>, <wchar.h>,
and <wctype.h>.

* configure.ac: don't check for <limits.h>, <string.h>, <time.h>, <assert.h>.
   Remove AC_INCLUDES_DEFAULT macro
* libguile/bytevectors.c: include <limits.h>, remove HAVE_LIMITS_H
* libguile/filesys.c: include <string.h>, remove HAVE_STRING_H
* libguile/fports.c: include <string.h>, remove HAVE_STRING_H
* libguile/gen-scmconfig.c: remove HAVE_LIMITS_H, HAVE_TIME_H, STDC_HEADERS
    Remove SCM_HAVE_STDC_HEADERS
* libguile/hash.c: include <wchar.h>, remove HAVE_WCHAR_H
* libguile/net_db.c: include <string.h>, remove HAVE_STRING_H
* libguile/numbers.h: remove SCM_HAVE_STDC_HEADERS
* libguile/regex-posix.c: include <wchar.h>, remove HAVE_WCHAR_H
  (fixup_multibyte_match): always defined
  (scm_regexp_exec): use fixup_multibyte_match
* libguile/scmsigs.c: remove STDC_HEADERS
* libguile/socket.c: include <string.h>, remove HAVE_STRING_H
* test-suite/standalone/test-unwind.c: include <string.h>, remove HAVE_STRING_H

10 files changed, 12 insertions, 56 deletions

diff --git a/libguile/bytevectors.c b/libguile/bytevectors.c
index f42fbb427..bbc23f449 100644
--- a/libguile/bytevectors.c
+++ b/libguile/bytevectors.c
@@ -22,10 +22,7 @@
 # include <config.h>
 #endif
 
-#ifdef HAVE_LIMITS_H
-# include <limits.h>
-#endif
-
+#include <limits.h>
 #include <byteswap.h>
 #include <errno.h>
 #include <striconveh.h>
diff --git a/libguile/filesys.c b/libguile/filesys.c
index 6247734e8..f182f6c79 100644
--- a/libguile/filesys.c
+++ b/libguile/filesys.c
@@ -43,6 +43,7 @@
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <unistd.h>
+#include <string.h>
 
 #ifdef HAVE_DIRECT_H
 #include <direct.h>
@@ -67,10 +68,6 @@
 #include <libc.h>
 #endif
 
-#ifdef HAVE_STRING_H
-#include <string.h>
-#endif
-
 #ifdef HAVE_PWD_H
 #include <pwd.h>
 #endif
diff --git a/libguile/fports.c b/libguile/fports.c
index 121d50bf0..9d4ca6ace 100644
--- a/libguile/fports.c
+++ b/libguile/fports.c
@@ -28,10 +28,7 @@
 
 #include <stdio.h>
 #include <fcntl.h>
-
-#ifdef HAVE_STRING_H
 #include <string.h>
-#endif
 #include <unistd.h>
 #ifdef HAVE_IO_H
 #include <io.h>
diff --git a/libguile/gen-scmconfig.c b/libguile/gen-scmconfig.c
index 691ebd0af..4525455b6 100644
--- a/libguile/gen-scmconfig.c
+++ b/libguile/gen-scmconfig.c
@@ -159,12 +159,7 @@ main (int argc, char *argv[])
   pf ("/* Important headers */\n");
   pf ("#include <stdint.h>\n");
   pf ("#include <stddef.h>\n");
-
-#ifdef HAVE_LIMITS_H
   pf ("#include <limits.h>\n");
-#else
-  pf ("/* limits.h not available */\n");
-#endif
 
 #if HAVE_SYS_TIME_H
   pf ("#include <sys/time.h>\n");
@@ -172,15 +167,9 @@ main (int argc, char *argv[])
   pf ("/* sys/time.h not available */\n");
 #endif
 
-#if HAVE_TIME_H
   pf ("#include <time.h>\n");
-#else
-  pf ("/* time.h not available */\n");
-#endif
-
   pf("\n");
-#ifdef STDC_HEADERS
-  pf ("#define SCM_HAVE_STDC_HEADERS 1 /* 0 or 1 */\n");
+
   pf ("#include <stdlib.h>\n");
 # ifdef HAVE_SYS_TYPES_H
   pf ("#include <sys/types.h>\n");
@@ -189,9 +178,6 @@ main (int argc, char *argv[])
   pf ("#include <sys/stdtypes.h>\n");
 # endif
   pf ("#include <stddef.h>\n");
-#else /* STDC_HEADERS */
-  pf ("#define SCM_HAVE_STDC_HEADERS 0 /* 0 or 1 */");
-#endif /* def STDC_HEADERS */
 
   pf("\n");
 #ifdef HAVE_SYS_SELECT_H
diff --git a/libguile/hash.c b/libguile/hash.c
index 11a35c2cb..c192ac2e5 100644
--- a/libguile/hash.c
+++ b/libguile/hash.c
@@ -24,10 +24,7 @@
 # include <config.h>
 #endif
 
-#ifdef HAVE_WCHAR_H
 #include <wchar.h>
-#endif
-
 #include <math.h>
 #include <string.h>
 #include <unistr.h>
diff --git a/libguile/net_db.c b/libguile/net_db.c
index dfb61e8d0..81e701668 100644
--- a/libguile/net_db.c
+++ b/libguile/net_db.c
@@ -33,11 +33,7 @@
 
 #include <verify.h>
 #include <errno.h>
-
-#ifdef HAVE_STRING_H
 #include <string.h>
-#endif
-
 #include <sys/types.h>
 
 #include <sys/socket.h>
diff --git a/libguile/numbers.h b/libguile/numbers.h
index fdb446e1a..84ad5466f 100644
--- a/libguile/numbers.h
+++ b/libguile/numbers.h
@@ -112,15 +112,13 @@ typedef long scm_t_inum;
  * SCM_FLTMAX is less than or scm_equal the largest single precision float
  */
 
-#if SCM_HAVE_STDC_HEADERS
-# ifndef GO32
-#  include <float.h>
-#  ifdef __MINGW32__
-#   define copysign _copysign
-#   define finite _finite
-#  endif /* __MINGW32__ */
-# endif /* ndef GO32 */
-#endif /* def STDC_HEADERS */
+#ifndef GO32
+# include <float.h>
+# ifdef __MINGW32__
+#  define copysign _copysign
+#  define finite _finite
+# endif /* __MINGW32__ */
+#endif /* ndef GO32 */
 
 #ifdef DBL_MAX_10_EXP
 # define SCM_MAXEXP DBL_MAX_10_EXP
diff --git a/libguile/regex-posix.c b/libguile/regex-posix.c
index a08da02db..5eb05c07c 100644
--- a/libguile/regex-posix.c
+++ b/libguile/regex-posix.c
@@ -35,10 +35,7 @@
 #include <regex.h>
 #include <string.h>
 #include <sys/types.h>
-
-#ifdef HAVE_WCHAR_H
 #include <wchar.h>
-#endif
 
 #include "async.h"
 #include "feature.h"
@@ -187,7 +184,6 @@ SCM_DEFINE (scm_make_regexp, "make-regexp", 1, 0, 1,
 }
 #undef FUNC_NAME
 
-#ifdef HAVE_WCHAR_H
 /*
  * While regexec does respect the current locale, it returns byte
  * offsets instead of character offsets. This routine fixes up the
@@ -222,7 +218,6 @@ fixup_multibyte_match (regmatch_t *matches, int nmatches, char *str)
     }
 
 }
-#endif
 
 SCM_DEFINE (scm_regexp_exec, "regexp-exec", 2, 2, 0,
             (SCM rx, SCM str, SCM start, SCM flags),
@@ -280,10 +275,8 @@ SCM_DEFINE (scm_regexp_exec, "regexp-exec", 2, 2, 0,
   status = regexec (SCM_RGX (rx), c_str, nmatches, matches,
 		    scm_to_int (flags));
 
-#ifdef HAVE_WCHAR_H
   if (!status)
     fixup_multibyte_match (matches, nmatches, c_str);
-#endif
 
   free (c_str);
 
diff --git a/libguile/scmsigs.c b/libguile/scmsigs.c
index d1daf04b4..5b8ffaf80 100644
--- a/libguile/scmsigs.c
+++ b/libguile/scmsigs.c
@@ -67,11 +67,7 @@
 #ifdef RETSIGTYPE
 # define SIGRETTYPE RETSIGTYPE
 #else
-# ifdef STDC_HEADERS
-#  define SIGRETTYPE void
-# else
-#  define SIGRETTYPE int
-# endif
+# define SIGRETTYPE void
 #endif
 
 
diff --git a/libguile/socket.c b/libguile/socket.c
index 8451aadac..446f7877f 100644
--- a/libguile/socket.c
+++ b/libguile/socket.c
@@ -30,9 +30,8 @@
 #ifdef HAVE_STDINT_H
 #include <stdint.h>
 #endif
-#ifdef HAVE_STRING_H
+
 #include <string.h>
-#endif
 #include <unistd.h>
 #include <sys/types.h>
 #include <sys/time.h>