From 209d5f8482d13a798f3ffd2faa6cbddb0f5b6724 Mon Sep 17 00:00:00 2001
From: Peter Zhu <peter@peterzhu.ca>
Date: Sat, 16 Sep 2023 09:08:55 -0400
Subject: [PATCH] Fix malloc_trim on emscripten

```
gc.c:9746:5: error: implicit declaration of function 'malloc_trim' is invalid in C99 [-Werror,-Wimplicit-function-declaration]
    malloc_trim(0);
    ^
```

http://rubyci.s3.amazonaws.com/crossruby/crossruby-master-wasm32_emscripten/log/20230916T104311Z.fail.html.gz
---
 gc.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/gc.c b/gc.c
index ffbbee7115..cc4406c0c9 100644
--- a/gc.c
+++ b/gc.c
@@ -48,7 +48,7 @@
 # endif
 #endif
 
-#if defined(HAVE_MALLOC_USABLE_SIZE) || defined(HAVE_MALLOC_TRIM)
+#ifdef HAVE_MALLOC_USABLE_SIZE
 # ifdef RUBY_ALTERNATIVE_MALLOC_HEADER
 /* Alternative malloc header is included in ruby/missing.h */
 # elif defined(HAVE_MALLOC_H)
@@ -60,6 +60,10 @@
 # endif
 #endif
 
+#ifdef HAVE_MALLOC_TRIM
+# include <malloc.h>
+#endif
+
 #if !defined(PAGE_SIZE) && defined(HAVE_SYS_USER_H)
 /* LIST_HEAD conflicts with sys/queue.h on macOS */
 # include <sys/user.h>