Fix build with newer C standard

Author: AMDmi3

exttests/cmake-shared/test.c

@@ -1,5 +1,5 @@
 #include <libversion/version.h>
 
-int main() {
+int main(void) {
 	return version_compare2("1.0", "1.1");
 }

exttests/cmake-static/test.c

@@ -1,5 +1,5 @@
 #include <libversion/version.h>
 
-int main() {
+int main(void) {
 	return version_compare2("1.0", "1.1");
 }

exttests/pkgconfig-shared/test.c

@@ -1,5 +1,5 @@
 #include <libversion/version.h>
 
-int main() {
+int main(void) {
 	return version_compare2("1.0", "1.1");
 }

exttests/pkgconfig-static/test.c

@@ -1,5 +1,5 @@
 #include <libversion/version.h>
 
-int main() {
+int main(void) {
 	return version_compare2("1.0", "1.1");
 }

tests/compare_fuzzer.c

@@ -26,7 +26,7 @@
 
 #include <stdio.h>
 
-int main() {
+int main(void) {
 	const char version_chars[] = { '0', '1', 'p', 'R', 'e', '.', '-' };
 	const size_t num_version_chars = sizeof(version_chars)/sizeof(version_chars[0]);
 

tests/compare_test.c

@@ -61,7 +61,7 @@ static int version_test_symmetrical(const char* v1, const char* v2, int expected
 	return version_test_symmetrical_flags(v1, v2, 0, 0, expected);
 }
 
-int main() {
+int main(void) {
 	int errors = 0;
 
 	fprintf(stderr, "Test group: equality\n");

utils/version_compare/version_compare.c

@@ -27,7 +27,7 @@
 #include <libversion/config.h>
 #include <libversion/version.h>
 
-static void print_version() {
+static void print_version(void) {
 	fprintf(stderr, "libversion %s\n", LIBVERSION_VERSION);
 }
 

utils/version_explain/version_explain.c

@@ -41,7 +41,7 @@ void version_explain(const char* v, int flags) {
     }
 }
 
-static void print_version() {
+static void print_version(void) {
 	fprintf(stderr, "libversion %s\n", LIBVERSION_VERSION);
 }