[PATCH] malloc: Cleanup warnings

[Wilco Dijkstra]

Cleanup warnings - malloc builds with -Os and -Og without needing any
complex warning avoidance defines.

---

diff --git a/malloc/malloc-check.c b/malloc/malloc-check.c
index fba7242190813d3b905d006fe039d2b6a22126b6..a78d79b6bde6ad113e3d6494bb296cb45f2541e1 100644
--- a/malloc/malloc-check.c
+++ b/malloc/malloc-check.c
@@ -314,12 +314,6 @@ realloc_check (void *oldmem, size_t bytes)
       newmem = _int_realloc (&main_arena, oldp, chunksize (oldp), chnb);
     }
 
-  DIAG_PUSH_NEEDS_COMMENT;
-#if __GNUC_PREREQ (7, 0)
-  /* GCC 7 warns about magic_p may be used uninitialized.  But we never
-     reach here if magic_p is uninitialized.  */
-  DIAG_IGNORE_NEEDS_COMMENT_GCC (7, "-Wmaybe-uninitialized");
-#endif
   /* mem2chunk_check changed the magic byte in the old chunk.
      If newmem is NULL, then the old chunk will still be used though,
      so we need to invert that change here.  */
diff --git a/malloc/malloc.c b/malloc/malloc.c
index 4aac196533d896353e3a32e34fa143d03eb82627..6455a1b0e0b85da0caaba4a5d922e1660fab5bb5 100644
--- a/malloc/malloc.c
+++ b/malloc/malloc.c
@@ -233,9 +233,6 @@
 /* For ALIGN_UP et. al.  */
 #include <libc-pointer-arith.h>
 
-/* For DIAG_PUSH/POP_NEEDS_COMMENT et al.  */
-#include <libc-diag.h>
-
 /* For memory tagging.  */
 #include <libc-mtag.h>
 
@@ -3099,7 +3096,7 @@ tcache_get_align (size_t nb, size_t alignment)
       tcache_entry **tep = & tcache->entries[tc_idx];
       tcache_entry *te = *tep;
       bool mangled = false;
-      size_t csize;
+      size_t csize = 0;
 
       while (te != NULL
 	     && ((csize = chunksize (mem2chunk (te))) < nb
@@ -3111,16 +3108,10 @@ tcache_get_align (size_t nb, size_t alignment)
           mangled = true;
         }
 
-      /* GCC compiling for -Os warns on some architectures that csize may be
-	 uninitialized.  However, if 'te' is not NULL, csize is always
-	 initialized in the loop above.  */
-      DIAG_PUSH_NEEDS_COMMENT;
-      DIAG_IGNORE_Os_NEEDS_COMMENT (12, "-Wmaybe-uninitialized");
       if (te != NULL
 	  && csize == nb
 	  && PTR_IS_ALIGNED (te, alignment))
 	return tag_new_usable (tcache_get_n (tc_idx, tep, mangled));
-      DIAG_POP_NEEDS_COMMENT;
     }
   return NULL;
 }