From: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date: Tue, 20 Jan 2026 13:11:10 +0000 (-0300)
Subject: arm: Fix tst-gnu2-tls2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ba0fedc2b9412792a410ca580da221f4e5c36599;p=thirdparty%2Fglibc.git

arm: Fix tst-gnu2-tls2

On armv7a vfpv4 tst-gnu2-tls2 fails with:

  open tst-gnu2-tls2mod0.so
  open tst-gnu2-tls2mod1.so
  open tst-gnu2-tls2mod2.so
  close tst-gnu2-tls2mod0.so
  close tst-gnu2-tls2mod1.so
  open tst-gnu2-tls2mod0.so
  open tst-gnu2-tls2mod1.so
  Didn't expect signal from child: got `Aborted'

Because AFTER_TLSDESC_CALL might clobber caller-saved registers and
the zero array might call the memset function resolution, which itself
might clobber some vector registers.

The AFTER_TLSDESC_CALL calls memset and memcmp, and both the
lazy resolution and the routines themselves can clobber the
caller-saved registes used in the tests.

Checked on arm-linux-gnueabihf (armv7-a vpfv4 / QEMU).

Reviewed-by: Florian Weimer <fweimer@redhat.com>
---

diff --git a/sysdeps/arm/tst-gnu2-tls2.h b/sysdeps/arm/tst-gnu2-tls2.h
index 821551c856..6fa98f83f6 100644
--- a/sysdeps/arm/tst-gnu2-tls2.h
+++ b/sysdeps/arm/tst-gnu2-tls2.h
@@ -77,27 +77,19 @@
       SAVE_VFP_D32					\
     }
 
-# define VFP_STACK_REQ (16*8)
-# if __BYTE_ORDER == __BIG_ENDIAN
-#  define DISP 7
-# else
-#  define DISP 0
-# endif
+# define VFP_STACK_REQ (16)
 
 # ifdef HAVE_ARM_PCS_VFP_D32
 #  define CHECK_VFP_D32							\
-      char vfp[VFP_STACK_REQ];						\
+      uint64_t vfp[VFP_STACK_REQ];					\
       asm volatile ("vstmia %0, {d16-d31}\n"				\
 		    :							\
 		    : "r" (vfp)						\
 		    : "memory");					\
 									\
-      char expected[VFP_STACK_REQ] = { 0 };				\
       for (int i = 0; i < 16; ++i)					\
-	expected[i * 8 + DISP] = i + 17;				\
-									\
-      if (memcmp (vfp, expected, VFP_STACK_REQ) != 0)			\
-        abort ();
+        if (vfp[i] != i + 17)						\
+	  abort ();
 # else
 #  define CHECK_VFP_D32
 # endif
@@ -105,18 +97,15 @@
 # define AFTER_TLSDESC_CALL()						\
   if (hwcap & HWCAP_ARM_VFP)						\
     {									\
-      char vfp[VFP_STACK_REQ];						\
+      uint64_t vfp[VFP_STACK_REQ];					\
       asm volatile ("vstmia %0, {d0-d15}\n"				\
 		    :							\
 		    : "r" (vfp)						\
 		    : "memory");					\
 									\
-      char expected[VFP_STACK_REQ] = { 0 };				\
       for (int i = 0; i < 16; ++i)					\
-	expected[i * 8 + DISP] = i + 1;					\
-									\
-      if (memcmp (vfp, expected, VFP_STACK_REQ) != 0)			\
-        abort ();							\
+        if (vfp[i] != i + 1)						\
+	  abort ();							\
     }									\
   if (hwcap & HWCAP_ARM_VFPD32)						\
     {									\