c-stack test fails on SPARC

[Sam James]

Hi,

This issue was noticed through grep 3.5 and 3.6’s stack-overflow test failing 
[0] on SPARC on Gentoo GNU/Linux.

Following Paul Eggert’s instructions in that bug to test gnulib’s c-stack 
component, I had the following
in /gltests/test-suite.log:

"FAIL: test-c-stack.sh
=====================

./test-c-stack.sh: line 7: 3238828 Segmentation fault      (core dumped) 
${CHECKER} ./test-c-stack${EXEEXT} 2> t-c-stack.tmp
FAIL test-c-stack.sh (exit status: 1)

I didn’t get much particularly useful out of gdb yet:

Reading symbols from ./test-c-stack...
(gdb) r
Starting program: /tmp/gnulib/foo/gltests/test-c-stack

Program received signal SIGSEGV, Segmentation fault.
0x0000010000000c64 in recurse_1 (n=<optimized out>, p=0xffffffffffffffff) at 
test-c-stack.c:35
35      {
(gdb) bt
#0  0x0000010000000c64 in recurse_1 (n=<optimized out>, p=0xffffffffffffffff) 
at test-c-stack.c:35
#1  0x0000000000000007 in ?? ()
Backtrace stopped: previous frame identical to this frame (corrupt stack?)"

The grep investigation was similar:

"(gdb) r
Starting program: /var/tmp/portage/sys-apps/grep-3.6/work/grep-3.6/src/grep -E 
-f in
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".

Program received signal SIGSEGV, Segmentation fault.
0x0000010000026908 in peek_token (token=0x10000aa9f30, input=0x10000aa9f30, 
syntax=1099522809648) at regcomp.c:1784
1784    {
(gdb) bt
#0  0x0000010000026908 in peek_token (token=0x10000aa9f30, input=0x10000aa9f30, 
syntax=1099522809648) at regcomp.c:1784
#1  0x0000010000aa9f38 in ?? ()
Backtrace stopped: previous frame inner to this frame (corrupt stack?)
(gdb)"

Please let me know what further information I can provide and how to better 
debug this, thanks a bunch!

[0] https://lists.gnu.org/archive/html/bug-grep/2021-02/msg00000.html.