Make ASAN default option string built-in libruby

The content depends on ruby internal, not responsibility of the
caller.  Revive `RUBY_GLOBAL_SETUP` macro to define the hook function.

Author: nobu

include/ruby/ruby.h

@@ -426,6 +426,14 @@ __extension__({ \
 # include "ruby/backward.h"
 #endif
 
+#ifndef RUBY__ASAN_DEFAULT_OPTIONS
+# define RUBY__ASAN_DEFAULT_OPTIONS
+#endif
+
+#define RUBY_GLOBAL_SETUP \
+    RUBY__ASAN_DEFAULT_OPTIONS \
+    /* RUBY_GLOBAL_SETUP end */
+
 RBIMPL_SYMBOL_EXPORT_END()
 
 #endif /* RUBY_RUBY_H */

internal/sanitizers.h

@@ -314,5 +314,17 @@ asan_get_fake_stack_extents(void *thread_fake_stack_handle, VALUE slot,
     return false;
 }
 
+extern const char ruby_asan_default_options[];
+
+#ifdef RUBY_ASAN_ENABLED
+/* Compile in the ASAN options Ruby needs, rather than relying on environment variables, so
+ * that even tests which fork ruby with a clean environment will run ASAN with the right
+ * settings */
+# undef RUBY__ASAN_DEFAULT_OPTIONS
+# define RUBY__ASAN_DEFAULT_OPTIONS \
+    RBIMPL_SYMBOL_EXPORT_BEGIN() \
+    const char * __asan_default_options(void) {return ruby_asan_default_options;} \
+    RBIMPL_SYMBOL_EXPORT_END()
+#endif
 
 #endif /* INTERNAL_SANITIZERS_H */

main.c

@@ -32,6 +32,8 @@
 # undef RUBY_DEBUG_ENV
 #endif
 
+RUBY_GLOBAL_SETUP
+
 static int
 rb_main(int argc, char **argv)
 {
@@ -64,16 +66,3 @@ main(int argc, char **argv)
     ruby_sysinit(&argc, &argv);
     return rb_main(argc, argv);
 }
-
-#ifdef RUBY_ASAN_ENABLED
-/* Compile in the ASAN options Ruby needs, rather than relying on environment variables, so
- * that even tests which fork ruby with a clean environment will run ASAN with the right
- * settings */
-RUBY_SYMBOL_EXPORT_BEGIN
-const char *
-__asan_default_options(void)
-{
-    return "use_sigaltstack=0:detect_leaks=0";
-}
-RUBY_SYMBOL_EXPORT_END
-#endif

ruby.c

@@ -3188,3 +3188,9 @@ ruby_sysinit(int *argc, char ***argv)
     }
     fill_standard_fds();
 }
+
+#ifdef RUBY_ASAN_ENABLED
+RUBY_SYMBOL_EXPORT_BEGIN
+const char ruby_asan_default_options[] = "use_sigaltstack=0:detect_leaks=0";
+RUBY_SYMBOL_EXPORT_END
+#endif