https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117667
Bug ID: 117667
Summary: -flto=auto prevents -fanalyzer from reporting any
warnings on a build of systemd
Product: gcc
Version: 15.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: analyzer
Assignee: dmalcolm at gcc dot gnu.org
Reporter: kdudka at redhat dot com
Target Milestone: ---
As originally reported by František Šumšal at
https://lists.fedoraproject.org/archives/list/[email protected]/message/2DXE6BMG3A3J72PDWUGZSEIKNHILUKR3/
-flto=auto prevents -fanalyzer from reporting any warnings on a build of
systemd.
Steps to reproduce:
1. compile/analyze without -flto=auto
% git clone https://github.com/systemd/systemd.git
% git reset --hard https://github.com/systemd/systemd.git
% CC=/opt/gcc-latest/bin/gcc meson build -Dc_args="-fanalyzer
-fdiagnostics-format=sarif-file"
% ninja -C build systemd
% find -name \*.sarif | xargs csgrep --mode=evtstat
1 COMPILER_WARNING
warning[-Wunterminated-string-initialization]
1 GCC_ANALYZER_WARNING
warning[-Wanalyzer-allocation-size]
34 GCC_ANALYZER_WARNING
warning[-Wanalyzer-double-free]
12 GCC_ANALYZER_WARNING
warning[-Wanalyzer-fd-leak]
1 GCC_ANALYZER_WARNING
warning[-Wanalyzer-fd-phase-mismatch]
1 GCC_ANALYZER_WARNING
warning[-Wanalyzer-file-leak]
1 GCC_ANALYZER_WARNING
warning[-Wanalyzer-infinite-loop]
100 GCC_ANALYZER_WARNING
warning[-Wanalyzer-malloc-leak]
1 GCC_ANALYZER_WARNING
warning[-Wanalyzer-mismatching-deallocation]
7 GCC_ANALYZER_WARNING
warning[-Wanalyzer-null-argument]
30 GCC_ANALYZER_WARNING
warning[-Wanalyzer-null-dereference]
21 GCC_ANALYZER_WARNING
warning[-Wanalyzer-out-of-bounds]
3 GCC_ANALYZER_WARNING
warning[-Wanalyzer-use-after-free]
57 GCC_ANALYZER_WARNING
warning[-Wanalyzer-use-of-uninitialized-value]
2 GCC_ANALYZER_WARNING
warning[-Wanalyzer-va-list-exhausted]
2. compile/analyze with -flto=auto
% git clean -dfx
% CC=/opt/gcc-latest/bin/gcc meson build -Dc_args="-fanalyzer
-fdiagnostics-format=sarif-file -flto=auto"
% ninja -C build systemd
% find -name \*.sarif | xargs csgrep --mode=evtstat
1 COMPILER_WARNING
warning[-Wunterminated-string-initialization]
That is, with -flto=auto, all the warnings from gcc analyzer silently disappear
(and the compilation runs apparently faster).
I am able to reproduce this with gcc-14.2.1-3.fc40.x86_64 as well as
gcc-latest-15.0.0-4.20241020git01f50ebfd97a.pr116613.v0.155.fc40.x86_64
installed from https://copr.fedorainfracloud.org/coprs/dmalcolm/gcc-latest/
