buildroot/package/uclibc/0001-include-stdlib.h-only-expose-reallocarray-prototype-.patch

From bbb1a4f197624b0040e3228505eb2a725a8846f8 Mon Sep 17 00:00:00 2001
From: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Date: Thu, 3 Apr 2025 22:56:49 +0200
Subject: [PATCH] include/stdlib.h: only expose reallocarray() prototype when
 implementation is available
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The reallocarray() primitive is only provided by the malloc-standard
implementation: neither malloc nor malloc-simple provide it. This
causes issues when building for example util-linux on noMMU platforms
as:

- noMMU platforms can't use malloc-standard, so either malloc or
  malloc-simple are used, which means reallocarray() is not
  implemented

- util-linux detects the absence of reallocarray(), and provides its
  own implementation, but the prototype clashes with the prototype in
  uClibc's <stdlib.h>

The combination of which causes the following build failure:

In file included from lib/color-names.c:7:
./include/c.h:586:21: error: static declaration of ‘reallocarray’ follows non-static declaration
  586 | static inline void *reallocarray(void *ptr, size_t nmemb, size_t size)
      |                     ^~~~~~~~~~~~
In file included from ./include/c.h:16:
/home/thomas/projets/buildroot/output/host/arm-buildroot-uclinux-uclibcgnueabi/sysroot/usr/include/stdlib.h:898:14: note: previous declaration of ‘reallocarray’ with type ‘void *(void *, size_t,  size_t)’ {aka ‘void *(void *, unsigned int,  unsigned int)’}
  898 | extern void *reallocarray (void *__ptr, size_t __m, size_t __n);
      |              ^~~~~~~~~~~~
make[3]: *** [Makefile:12354: lib/libtcolors_la-color-names.lo] Error 1

To fix this, let's not expose the prototype of reallocarray() if we
don't provide the implementation for it.

Upstream: https://mailman.openadk.org/mailman3/hyperkitty/list/devel@uclibc-ng.org/thread/BX4ENNZYO23YQJQF5XITW7TETSJHEFK5/
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
---
 include/stdlib.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/include/stdlib.h b/include/stdlib.h
index d4e0b75e7..448c5e336 100644
--- a/include/stdlib.h
+++ b/include/stdlib.h
@@ -986,9 +986,13 @@ extern int getpt (void);
 extern int getloadavg (double __loadavg[], int __nelem)
      __THROW __nonnull ((1));
 
+/* reallocarray() only provided by the malloc-standard implementation */
+#if defined(__MALLOC_STANDARD__)
 extern void *reallocarray (void *__ptr, size_t __m, size_t __n);
 #endif
 
+#endif
+
 #ifdef _LIBC
 extern int __drand48_iterate (unsigned short int xsubi[3], struct drand48_data *buffer) attribute_hidden;
 
-- 
2.48.1