Drop use of obsoleted autoconf AC_HEADER_STDC macro. Fixes #409

Use of the STDC_HEADER pre-processor macro that the autoconf macro
used to define has been removed.  Conditionalized code is now used
unconditionally.  This should be fine as the macro checks for ANSI
C, i.e. C89 (ISO C90), compliant headers.  We already require C99.

acinclude.m4

@@ -73,9 +73,6 @@ AC_DEFUN([SANE_CHECK_MISSING_HEADERS],
   if test "${ac_cv_header_unistd_h}" != "yes" ; then
     MISSING_HEADERS="${MISSING_HEADERS}\"unistd.h\" "
   fi
-  if test "${ac_cv_header_stdc}" != "yes" ; then
-    MISSING_HEADERS="${MISSING_HEADERS}\"ANSI C headers\" "
-  fi
   if test "${MISSING_HEADERS}" != "" ; then
     echo "*** The following essential header files couldn't be found:"
     echo "*** ${MISSING_HEADERS}"

lib/md5.c

@@ -26,14 +26,8 @@
 
 #include <sys/types.h>
 
-#if STDC_HEADERS || defined _LIBC
-# include <stdlib.h>
-# include <string.h>
-#else
-# ifndef HAVE_MEMCPY
-#  define memcpy(d, s, n) bcopy ((s), (d), (n))
-# endif
-#endif
+#include <stdlib.h>
+#include <string.h>
 
 #include "md5.h"
 

sanei/sanei_pa4s2.c

@@ -150,11 +150,9 @@ static int sanei_pa4s2_dbg_init_called = SANE_FALSE;
 
 #endif /* NDEBUG */
 
-#if defined(STDC_HEADERS)
-# include <errno.h>
-# include <stdio.h>
-# include <stdlib.h>
-#endif
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
 #if defined(HAVE_STRING_H)
 # include <string.h>
 #elif defined(HAVE_STRINGS_H)

sanei/sanei_pp.c

@@ -135,11 +135,9 @@ inb( u_long port )
 #include "../include/sane/sanei_debug.h"
 #include "../include/sane/sanei_pp.h"
 
-#if defined(STDC_HEADERS)
-# include <errno.h>
-# include <stdio.h>
-# include <stdlib.h>
-#endif
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
 #if defined(HAVE_STRING_H)
 # include <string.h>
 #elif defined(HAVE_STRINGS_H)