[RFC PATCH 5/5] Revert "meson.build: Disable -fzero-call-used-regs on OpenBSD"

[Thomas Huth <thuth@redhat.com>]

From: Thomas Huth <thuth@redhat.com>

This reverts commit 2d6d995709482cc8b6a76dbb5334a28001a14a9a.

OpenBSD 7.7 fixed the problem with the -fzero-call-used-regs on OpenBSD,
see https://github.com/openbsd/src/commit/03eca72d1e030b7a542cd6aec1 for
the fix there.

Suggested-by: Brad Smith <brad@comstyle.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 Note: Marked as RFC since we likely can include this only once OpenBSD
 7.6 goes out of service, see:
 https://lists.libreplanet.org/archive/html/qemu-arm/2025-05/msg00559.html

 meson.build | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/meson.build b/meson.build
index 6c61e1dcaec..5f0e6a65cb0 100644
--- a/meson.build
+++ b/meson.build
@@ -699,11 +699,7 @@ hardening_flags = [
 #
 # NB: Clang 17 is broken and SEGVs
 # https://github.com/llvm/llvm-project/issues/75168
-#
-# NB2: This clashes with the "retguard" extension of OpenBSD's Clang
-# https://gitlab.com/qemu-project/qemu/-/issues/2278
-if host_os != 'openbsd' and \
-   cc.compiles('extern struct { void (*cb)(void); } s; void f(void) { s.cb(); }',
+if cc.compiles('extern struct { void (*cb)(void); } s; void f(void) { s.cb(); }',
                name: '-fzero-call-used-regs=used-gpr',
                args: ['-O2', '-fzero-call-used-regs=used-gpr'])
     hardening_flags += '-fzero-call-used-regs=used-gpr'
-- 
2.49.0