From 7415a0fa4abc1b8e8af37afd5b5408c1d5dfff2e Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert@cs.ucla.edu>
Date: Sat, 17 Apr 2021 18:48:38 -0700
Subject: [PATCH 2/2] xalloc: adjust to malloc ptrdiff_t change

* lib/xmalloc.c (HAVE_GNU_CALLOC, HAVE_GNU_MALLOC, HAVE_GNU_REALLOC):
Remove.
(xmalloc, xrealloc, xcalloc): Simplify by assuming GNU behavior.
* modules/xalloc (Depends-on): Add calloc-gnu, malloc-gnu,
realloc-gnu.
---
 ChangeLog      |  7 +++++++
 lib/xmalloc.c  | 41 ++++-------------------------------------
 modules/xalloc |  3 +++
 3 files changed, 14 insertions(+), 37 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 825201fe2..03221a292 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,12 @@
 2021-04-17  Paul Eggert  <eggert@cs.ucla.edu>
 
+	xalloc: adjust to malloc ptrdiff_t change
+	* lib/xmalloc.c (HAVE_GNU_CALLOC, HAVE_GNU_MALLOC, HAVE_GNU_REALLOC):
+	Remove.
+	(xmalloc, xrealloc, xcalloc): Simplify by assuming GNU behavior.
+	* modules/xalloc (Depends-on): Add calloc-gnu, malloc-gnu,
+	realloc-gnu.
+
 	malloc, etc.: check for ptrdiff_t overflow
 	In glibc 2.30 and later, malloc, realloc and calloc reject
 	attempts to create objects larger than PTRDIFF_MAX bytes.
diff --git a/lib/xmalloc.c b/lib/xmalloc.c
index 4a6589571..39ce893ad 100644
--- a/lib/xmalloc.c
+++ b/lib/xmalloc.c
@@ -27,34 +27,13 @@
 #include <stdlib.h>
 #include <string.h>
 
-/* 1 if calloc, malloc and realloc are known to be compatible with GNU.
-   This matters if we are not also using the calloc-gnu, malloc-gnu
-   and realloc-gnu modules, which define HAVE_CALLOC_GNU,
-   HAVE_MALLOC_GNU and HAVE_REALLOC_GNU and support the GNU API even
-   on non-GNU platforms.  */
-#if defined HAVE_CALLOC_GNU || (defined __GLIBC__ && !defined __UCLIBC__)
-enum { HAVE_GNU_CALLOC = 1 };
-#else
-enum { HAVE_GNU_CALLOC = 0 };
-#endif
-#if defined HAVE_MALLOC_GNU || (defined __GLIBC__ && !defined __UCLIBC__)
-enum { HAVE_GNU_MALLOC = 1 };
-#else
-enum { HAVE_GNU_MALLOC = 0 };
-#endif
-#if defined HAVE_REALLOC_GNU || (defined __GLIBC__ && !defined __UCLIBC__)
-enum { HAVE_GNU_REALLOC = 1 };
-#else
-enum { HAVE_GNU_REALLOC = 0 };
-#endif
-
 /* Allocate N bytes of memory dynamically, with error checking.  */
 
 void *
 xmalloc (size_t n)
 {
   void *p = malloc (n);
-  if (!p && (HAVE_GNU_MALLOC || n))
+  if (!p)
     xalloc_die ();
   return p;
 }
@@ -65,15 +44,8 @@ xmalloc (size_t n)
 void *
 xrealloc (void *p, size_t n)
 {
-  if (!HAVE_GNU_REALLOC && !n && p)
-    {
-      /* The GNU and C99 realloc behaviors disagree here.  Act like GNU.  */
-      free (p);
-      return NULL;
-    }
-
   void *r = realloc (p, n);
-  if (!r && (n || (HAVE_GNU_REALLOC && !p)))
+  if (!r && (!p || n))
     xalloc_die ();
   return r;
 }
@@ -175,13 +147,8 @@ xzalloc (size_t n)
 void *
 xcalloc (size_t n, size_t s)
 {
-  void *p;
-  /* Test for overflow, since objects with size greater than
-     PTRDIFF_MAX cause pointer subtraction to go awry.  Omit size-zero
-     tests if HAVE_GNU_CALLOC, since GNU calloc never returns NULL if
-     successful.  */
-  if (xalloc_oversized (n, s)
-      || (! (p = calloc (n, s)) && (HAVE_GNU_CALLOC || n != 0)))
+  void *p = calloc (n, s);
+  if (!p)
     xalloc_die ();
   return p;
 }
diff --git a/modules/xalloc b/modules/xalloc
index 5fa386a5d..000933e94 100644
--- a/modules/xalloc
+++ b/modules/xalloc
@@ -8,10 +8,13 @@ m4/xalloc.m4
 
 Depends-on:
 c99
+calloc-gnu
 extern-inline
 idx
 intprops
+malloc-gnu
 minmax
+realloc-gnu
 stdint
 xalloc-die
 xalloc-oversized
-- 
2.27.0