[PATCH 2/2] meson: Enable -Wvla

[Peter Maydell]

QEMU has historically used variable length arrays only very rarely.
Variable length arrays are a potential security issue where an
on-stack dynamic allocation isn't correctly size-checked, especially
when the size comes from the guest.  (An example problem of this kind
from the past is CVE-2021-3527).  Forbidding them entirely is a
defensive measure against further bugs of this kind.

Enable -Wvla to prevent any new uses from sneaking into the codebase.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 meson.build | 1 +
 1 file changed, 1 insertion(+)

diff --git a/meson.build b/meson.build
index d0329966f1b..385b8247073 100644
--- a/meson.build
+++ b/meson.build
@@ -601,6 +601,7 @@ warn_flags = [
   '-Wno-psabi',
   '-Wno-gnu-variable-sized-type-not-at-end',
   '-Wshadow=local',
+  '-Wvla',
 ]
 
 if host_os != 'darwin'
-- 
2.34.1