Re: [libvirt PATCH 1/6] meson: Allow larger stack frames when instrumenting
On Mon, May 03, 2021 at 12:01:41PM +0200, Tim Wiederhake wrote:
When enabling sanitizers, gcc adds some instrumentation to the code
that may enlarge stack frames. Some function's stack frames are already
close to the limit of 4096 and are enlarged past that threshold,
e.g. virLXCProcessStart which reaches a frame size of 4624 bytes.
Signed-off-by: Tim Wiederhake <twiederh(a)redhat.com>
---
meson.build | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/meson.build b/meson.build
index 618cbd6b1d..bbdbe4afd8 100644
--- a/meson.build
+++ b/meson.build
@@ -278,7 +278,8 @@ cc_flags += [
'-Wformat-y2k',
'-Wformat-zero-length',
'-Wframe-address',
- '-Wframe-larger-than=4096',
+ # sanitizer instrumentation may enlarge stack frames
+ '-Wframe-larger-than=@0(a)'.format(get_option('b_sanitize') in
['', 'none'] ? 4096 : 8192),
'-Wfree-nonheap-object',
'-Whsa',
'-Wif-not-aligned',
Looks good but needs some polishing. I would do something similar to
what we do with -Walloc-size-larger-than:
# sanitizer instrumentation may enlarge stack frames
stack_frame_size = get_option('b_sanitize') == 'none' ? 4096 : 8192
cc_flags += [
...
'-Wframe-larger-than=@0(a)'.format(stack_frame_size),
...
]
In addition there is no need to check for empty string as meson will
handle that while parsing the command argument. All of the following
commands:
meson build -Db_sanitize=
meson build -Db_sanitize=""
meson build -Db_sanitize=" "
meson build -Db_sanitize="asdf"
result in this error (the value in the error message reflects the one
actually used):
meson.build:1:0: ERROR: Value "" (of type "string") for combo
option "Code sanitizer to use" is not one of the choices. Possible choices are
(as string): "none", "address", "thread",
"undefined", "memory", "address,undefined".
Pavel
Attachments:
- signature.asc (application/pgp-signature — 833 bytes)