fix build with musl

malloc.c

@@ -1049,9 +1049,11 @@ EXPORT int h_malloc_trim(UNUSED size_t pad) {
 
 EXPORT void h_malloc_stats(void) {}
 
+#if defined(__GLIBC__) || defined(__ANDROID__)
 EXPORT struct mallinfo h_mallinfo(void) {
     return (struct mallinfo){0};
 }
+#endif
 
 EXPORT int h_malloc_info(UNUSED int options, UNUSED FILE *fp) {
     errno = ENOSYS;

malloc.h

@@ -51,7 +51,9 @@ size_t h_malloc_usable_size(void *ptr);
 int h_mallopt(int param, int value);
 int h_malloc_trim(size_t pad);
 void h_malloc_stats(void);
+#if defined(__GLIBC__) || defined(__ANDROID__)
 struct mallinfo h_mallinfo(void);
+#endif
 int h_malloc_info(int options, FILE *fp);
 
 // obsolete glibc extensions