[glibc] malloc: Fix tst-tcfree3 build csky-linux-gnuabiv2 with fortify source

[Adhemerval Zanella <azanella@sourceware.org>]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=83d13972f23546758b600ba940e0d53248dd0339

commit 83d13972f23546758b600ba940e0d53248dd0339
Author: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date:   Mon Oct 23 13:33:47 2023 -0300

    malloc: Fix tst-tcfree3 build csky-linux-gnuabiv2 with fortify source
    
    With gcc 13.1 with --enable-fortify-source=2, tst-tcfree3 fails to
    build on csky-linux-gnuabiv2 with:
    
    ../string/bits/string_fortified.h: In function ‘do_test’:
    ../string/bits/string_fortified.h:26:8: error: inlining failed in call
    to ‘always_inline’ ‘memcpy’: target specific option mismatch
       26 | __NTH (memcpy (void *__restrict __dest, const void *__restrict
          __src,
          |        ^~~~~~
    ../misc/sys/cdefs.h:81:62: note: in definition of macro ‘__NTH’
       81 | #  define __NTH(fct)    __attribute__ ((__nothrow__ __LEAF)) fct
          |                                                              ^~~
    tst-tcfree3.c:45:3: note: called from here
       45 |   memcpy (c, a, 32);
          |   ^~~~~~~~~~~~~~~~~
    
    Instead of relying on -O0 to avoid malloc/free to be optimized away,
    disable the builtin.
    
    Reviewed-by: DJ Delorie <dj@redhat.com>

Diff:
---
 malloc/Makefile      | 2 ++
 malloc/tst-tcfree3.c | 3 ---
 2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/malloc/Makefile b/malloc/Makefile
index c1db3347d8..f6cdf7bf0b 100644
--- a/malloc/Makefile
+++ b/malloc/Makefile
@@ -298,6 +298,8 @@ CPPFLAGS-malloc.c += -DUSE_TCACHE=1
 # Uncomment this for test releases.  For public releases it is too expensive.
 #CPPFLAGS-malloc.o += -DMALLOC_DEBUG=1
 
+CFLAGS-tst-tcfree3.c += -fno-builtin-malloc -fno-builtin-free
+
 sLIBdir := $(shell echo $(slibdir) | sed 's,lib\(\|64\)$$,\\\\$$LIB,')
 
 $(objpfx)mtrace: mtrace.pl
diff --git a/malloc/tst-tcfree3.c b/malloc/tst-tcfree3.c
index ce6d958f8a..30886b6f49 100644
--- a/malloc/tst-tcfree3.c
+++ b/malloc/tst-tcfree3.c
@@ -19,9 +19,6 @@
 #include <malloc.h>
 #include <string.h>
 
-/* Prevent GCC from optimizing away any malloc/free pairs.  */
-#pragma GCC optimize ("O0")
-
 static int
 do_test (void)
 {