Paul Eggert wrote:
> # Test whether malloc, realloc, calloc refuse to create objects
> # larger than what can be expressed in ptrdiff_t.
> -# Set gl_cv_func_malloc_gnu to yes or no accordingly.
> +# Set gl_cv_func_malloc_gnu and define MALLOC_PTRDIFF accordingly.
> AC_DEFUN([gl_CHECK_MALLOC_PTRDIFF],
This comment is incorrect, as it's the other macro that defines
HAVE_MALLOC_PTRDIFF, not this one.
Fixed as follows:
2024-11-05 Bruno Haible <br...@clisp.org>
calloc, malloc: Fix a comment.
* m4/malloc.m4 (gl_FUNC_MALLOC_GNU): Mention that it sets
HAVE_MALLOC_PTRDIFF.
(gl_FUNC_MALLOC_PTRDIFF): Likewise.
(gl_CHECK_MALLOC_PTRDIFF): Do not mention HAVE_MALLOC_PTRDIFF here.
diff --git a/m4/malloc.m4 b/m4/malloc.m4
index deb0de24de..bad5ee9501 100644
--- a/m4/malloc.m4
+++ b/m4/malloc.m4
@@ -1,5 +1,5 @@
# malloc.m4
-# serial 41
+# serial 42
dnl Copyright (C) 2007, 2009-2024 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
@@ -45,8 +45,12 @@ AC_DEFUN([_AC_FUNC_MALLOC_IF]
# gl_FUNC_MALLOC_GNU
# ------------------
-# Define HAVE_MALLOC_0_NONNULL if malloc (0) returns nonnull.
-# Replace malloc if it is not compatible with GNU libc.
+# Test whether malloc (0) is compatible with GNU libc.
+# Replace malloc if not.
+# Define HAVE_MALLOC_0_NONNULL if malloc (0) returns nonnull (except upon
+# out-of-memory).
+# Define HAVE_MALLOC_PTRDIFF if malloc (N) reliably fails when N exceeds
+# PTRDIFF_MAX.
AC_DEFUN([gl_FUNC_MALLOC_GNU],
[
AC_REQUIRE([gl_STDLIB_H_DEFAULTS])
@@ -66,8 +70,9 @@ AC_DEFUN([gl_FUNC_MALLOC_GNU]
# gl_FUNC_MALLOC_PTRDIFF
# ----------------------
-# Test whether malloc (N) reliably fails when N exceeds PTRDIFF_MAX,
-# and replace malloc otherwise.
+# Test whether malloc (N) reliably fails when N exceeds PTRDIFF_MAX.
+# Define HAVE_MALLOC_PTRDIFF if yes.
+# Replace malloc if not.
AC_DEFUN([gl_FUNC_MALLOC_PTRDIFF],
[
AC_REQUIRE([gl_STDLIB_H_DEFAULTS])
@@ -81,7 +86,7 @@ AC_DEFUN([gl_FUNC_MALLOC_PTRDIFF]
# Test whether malloc, realloc, calloc refuse to create objects
# larger than what can be expressed in ptrdiff_t.
-# Set gl_cv_func_malloc_gnu and define MALLOC_PTRDIFF accordingly.
+# Set gl_cv_func_malloc_gnu.
AC_DEFUN([gl_CHECK_MALLOC_PTRDIFF],
[
AC_CACHE_CHECK([whether malloc is ptrdiff_t safe],
