Modernize the C style of those autoconf tests.

The intent is to produce fewer warnings when configuring with -verbose.
Note that the warning on "implicit declaration of function" remains,
for relatively good reasons.


git-svn-id: http://caml.inria.fr/svn/ocaml/branches/cc-optim@16330 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02

Author: xavierleroy

config/auto-aux/dblalign.c

@@ -15,9 +15,9 @@
 #include <signal.h>
 #include <setjmp.h>
 
-double foo;
+volatile double foo;
 
-void access_double(double *p)
+void access_double(volatile double *p)
 {
   foo = *p;
 }
@@ -38,8 +38,8 @@ int main(void)
   signal(SIGBUS, sig_handler);
 #endif
   if(setjmp(failure) == 0) {
-    access_double((double *) n);
-    access_double((double *) (n+1));
+    access_double((volatile double *) n);
+    access_double((volatile double *) (n+1));
     res = 0;
   } else {
     res = 1;
@@ -48,5 +48,5 @@ int main(void)
 #ifdef SIGBUS
   signal(SIGBUS, SIG_DFL);
 #endif
-  exit(res);
+  return res;
 }

config/auto-aux/endian.c

@@ -11,6 +11,7 @@
 /*                                                                     */
 /***********************************************************************/
 
+#include <string.h>
 #include "m.h"
 
 #ifndef ARCH_SIXTYFOUR
@@ -23,7 +24,7 @@ char * bigendian = "ABCDEFGH";
 char * littleendian = "HGFEDCBA";
 #endif
 
-main(void)
+int main(void)
 {
   long n[2];
   char * p;
@@ -32,8 +33,8 @@ main(void)
   n[1] = 0;
   p = (char *) n;
   if (strcmp(p, bigendian) == 0)
-    exit(0);
+    return 0;
   if (strcmp(p, littleendian) == 0)
-    exit(1);
-  exit(2);
+    return 1;
+  return 2;
 }

config/auto-aux/hasgot

@@ -30,9 +30,9 @@ while : ; do
   shift
 done
 
-(echo "main() {"
+(echo "int main() {"
  for f in $*; do echo "  $f();"; done
- echo "}") >> hasgot.c
+ echo "  return 0; }") >> hasgot.c
 
 if test "$verbose" = yes; then
   echo "hasgot $args: $cc $opts -o tst hasgot.c $libs" >&2

config/auto-aux/hasgot2

@@ -30,9 +30,9 @@ while : ; do
   shift
 done
 
-(echo "main() {"
+(echo "int main() {"
  for f in $*; do echo "  (void) & $f;"; done
- echo "}") >> hasgot.c
+ echo "  return 0; }") >> hasgot.c
 
 if test "$verbose" = yes; then
   echo "hasgot2 $args: $cc $opts -o tst hasgot.c $libs" >&2

config/auto-aux/int64align.c

@@ -26,9 +26,9 @@ typedef long long int64_t;
 #error "No 64-bit integer type available"
 #endif
 
-int64_t foo;
+volatile int64_t foo;
 
-void access_int64(int64_t *p)
+void access_int64(volatile int64_t *p)
 {
   foo = *p;
 }
@@ -49,8 +49,8 @@ int main(void)
   signal(SIGBUS, sig_handler);
 #endif
   if(setjmp(failure) == 0) {
-    access_int64((int64_t *) n);
-    access_int64((int64_t *) (n+1));
+    access_int64((volatile int64_t *) n);
+    access_int64((volatile int64_t *) (n+1));
     res = 0;
   } else {
     res = 1;
@@ -59,5 +59,5 @@ int main(void)
 #ifdef SIGBUS
   signal(SIGBUS, SIG_DFL);
 #endif
-  exit(res);
+  return res;
 }

config/auto-aux/sizes.c

@@ -16,7 +16,10 @@
 int main(int argc, char **argv)
 {
   printf("%d %d %d %d %d\n",
-         sizeof(int), sizeof(long), sizeof(long *), sizeof(short),
-         sizeof(long long));
+         (int) sizeof(int),
+         (int) sizeof(long),
+         (int) sizeof(long *),
+         (int) sizeof(short),
+         (int) sizeof(long long));
   return 0;
 }