mirror of
https://github.com/gcc-mirror/gcc.git
synced 2026-05-06 14:59:39 +02:00
9b4eee5fd1
GCC 12 has gained two features for dealing with uninitialized variables:
(a) a new -Wanalyzer-use-of-uninitialized-value warning within -fanalyzer
for interprocedural path-sensitive detection of ununit uses, and
(b) a new -ftrivial-auto-var-init option for mitigating some uses of
uninit variables
It turns out that using (b) was thwarting (a), as it led to -fanalyzer
seeing calls to IFN_DEFERRED_INIT, which -fanalyzer wasn't
special-casing, thus treating it as initializing the variables in
question, and thus silencing -Wanalyzer-use-of-uninitialized-value on
them.
invoke.texi says:
"GCC still considers an automatic variable that doesn't have an explicit
initializer as uninitialized, @option{-Wuninitialized} will still report
warning messages on such automatic variables."
and thus -Wanalyzer-use-of-uninitialized-value ought to as well.
This patch adds special-case handling to -fanalyzer for
IFN_DEFERRED_INIT, so that -fanalyzer will warn on uninit uses of
variables that are mitigated by -ftrivial-auto-var-init.
gcc/analyzer/ChangeLog:
PR analyzer/104270
* region-model.cc (region_model::on_call_pre): Handle
IFN_DEFERRED_INIT.
gcc/testsuite/ChangeLog:
PR analyzer/104270
* gcc.dg/analyzer/uninit-trivial-auto-var-init-pattern.c: New
test.
* gcc.dg/analyzer/uninit-trivial-auto-var-init-uninitialized.c:
New test.
* gcc.dg/analyzer/uninit-trivial-auto-var-init-zero.c: New test.
Signed-off-by: David Malcolm <dmalcolm@redhat.com>
This directory contains the GNU Compiler Collection (GCC). The GNU Compiler Collection is free software. See the files whose names start with COPYING for copying permission. The manuals, and some of the runtime libraries, are under different terms; see the individual source files for details. The directory INSTALL contains copies of the installation information as HTML and plain text. The source of this information is gcc/doc/install.texi. The installation information includes details of what is included in the GCC sources and what files GCC installs. See the file gcc/doc/gcc.texi (together with other files that it includes) for usage and porting information. An online readable version of the manual is in the files gcc/doc/gcc.info*. See http://gcc.gnu.org/bugs/ for how to report bugs usefully. Copyright years on GCC source files may be listed using range notation, e.g., 1987-2012, indicating that every year in the range, inclusive, is a copyrightable year that could otherwise be listed individually.