Fixed main() prototypes in auto tests.

Future releases of GCC are planning to remove[0] default support for
some old features that were removed from C99 but GCC still accepts.

We can test for these changes by using the following -Werror=
directives

  -Werror=implicit-int
  -Werror=implicit-function-declaration
  -Werror=int-conversion
  -Werror=strict-prototypes
  -Werror=old-style-definition

Doing so revealed an issue with the auto/ tests in that the test
programs always define main as

  int main()

rather than

  int main(void)

which results in a bunch of errors like

build/autotest.c:3:23: error: function declaration isn't a prototype [-Werror=strict-prototypes]
    3 |                   int main() {
      |                       ^~~~
build/autotest.c: In function 'main':
build/autotest.c:3:23: error: old-style function definition [-Werror=old-style-definition]

The fix was easy, it only required fixing the main prototype with

  find -type f -exec sed -i 's/int main() {/int main(void) {/g' {} \;

Regardless of these upcoming GCC changes, this is probably a good thing
to do anyway for correctness.

[0]: https://fedoraproject.org/wiki/Changes/PortingToModernC

Link: <https://lists.fedoraproject.org/archives/list/devel@lists.fedoraproject.org/message/CJXKTLXJUPZ4F2C2VQOTNMEA5JAUPMBD/>
Link: <https://lists.fedoraproject.org/archives/list/devel@lists.fedoraproject.org/message/6SGHPHPAXKCVJ6PUZ57WVDQ5TDBVIRMF/>
Reviewed-by: Alejandro Colomar <alx@nginx.com>
Signed-off-by: Andrew Clayton <a.clayton@nginx.com>

1 files changed, 4 insertions, 4 deletions

diff --git a/auto/modules/php b/auto/modules/php
index 7d224ec1..f0ecb709 100644
--- a/auto/modules/php
+++ b/auto/modules/php
@@ -131,7 +131,7 @@ nxt_feature_libs="${NXT_PHP_LIB} ${NXT_PHP_LDFLAGS}"
 nxt_feature_test="
     #include <php.h>
 
-    int main() {
+    int main(void) {
         printf(\"%s\", PHP_VERSION);
         return 0;
     }"
@@ -148,7 +148,7 @@ nxt_feature_test="
     #include <php.h>
     #include <php_main.h>
 
-    int main() {
+    int main(void) {
     #if (PHP_VERSION_ID < 80200)
         php_module_startup(NULL, NULL, 0);
     #else
@@ -176,7 +176,7 @@ nxt_feature_test="
     #include <php.h>
     #include <php_main.h>
 
-    int main() {
+    int main(void) {
         #ifndef ZTS
         #error ZTS is not defined.
         #endif
@@ -197,7 +197,7 @@ nxt_feature_test="
     #include <php.h>
     #include <php_main.h>
 
-    int main() {
+    int main(void) {
         zend_signal_startup();
         return 0;
     }"