[Bug c++/79882] New: Lack of bounds checking on -ftemplate-depth argument
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79882 Bug ID: 79882 Summary: Lack of bounds checking on -ftemplate-depth argument Product: gcc Version: 5.4.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: pefoley2 at pefoley dot com Target Milestone: --- -ftemplate-depth appears to not check for overflow: gcc -v Using built-in specs. COLLECT_GCC=/usr/x86_64-pc-linux-gnu/gcc-bin/5.4.0/gcc COLLECT_LTO_WRAPPER=/usr/libexec/gcc/x86_64-pc-linux-gnu/5.4.0/lto-wrapper Target: x86_64-pc-linux-gnu Configured with: /var/tmp/portage/sys-devel/gcc-5.4.0-r3/work/gcc-5.4.0/configure --host=x86_64-pc-linux-gnu --build=x86_64-pc-linux-gnu --prefix=/usr --bindir=/usr/x86_64-pc-linux-gnu/gcc-bin/5.4.0 --includedir=/usr/lib/gcc/x86_64-pc-linux-gnu/5.4.0/include --datadir=/usr/share/gcc-data/x86_64-pc-linux-gnu/5.4.0 --mandir=/usr/share/gcc-data/x86_64-pc-linux-gnu/5.4.0/man --infodir=/usr/share/gcc-data/x86_64-pc-linux-gnu/5.4.0/info --with-gxx-include-dir=/usr/lib/gcc/x86_64-pc-linux-gnu/5.4.0/include/g++-v5 --with-python-dir=/share/gcc-data/x86_64-pc-linux-gnu/5.4.0/python --enable-languages=c,c++,go,fortran --enable-obsolete --enable-secureplt --disable-werror --with-system-zlib --enable-nls --without-included-gettext --enable-checking=release --with-bugurl=https://bugs.gentoo.org/ --with-pkgversion='Gentoo 5.4.0-r3 p1.3, pie-0.6.5' --enable-libstdcxx-time --enable-shared --enable-threads=posix --enable-__cxa_atexit --enable-clocale=gnu --enable-multilib --with-multilib-list=m32,m64 --disable-altivec --disable-fixed-point --enable-targets=all --disable-libgcj --enable-libgomp --disable-libmudflap --disable-libssp --enable-libcilkrts --disable-libmpx --enable-vtable-verify --enable-libvtv --enable-lto --with-isl --disable-isl-version-check --enable-libsanitizer Thread model: posix gcc version 5.4.0 (Gentoo 5.4.0-r3 p1.3, pie-0.6.5) g++ -std=c++11 -ftemplate-depth=4294967296 a.cc a.cc: In function ‘int main()’: a.cc:12:26: fatal error: template instantiation depth exceeds maximum of 0 (use -ftemplate-depth= to increase the maximum) g++ -std=c++11 -ftemplate-depth=4294967297 a.cc a.cc: In instantiation of ‘struct meme<2147483648u, int>’: a.cc:12:26: required from here a.cc:3:20: fatal error: template instantiation depth exceeds maximum of 1 (use -ftemplate-depth= to increase the maximum)
[Bug c/108402] New: False positive Wuninitialized with ftrivial-auto-var-init=pattern
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108402 Bug ID: 108402 Summary: False positive Wuninitialized with ftrivial-auto-var-init=pattern Product: gcc Version: 12.2.1 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c Assignee: unassigned at gcc dot gnu.org Reporter: pefoley2 at pefoley dot com Target Milestone: --- Created attachment 54271 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=54271&action=edit Reduced test case This error showed up when compiling the upstream Linux kernel with ARCH=um allyesconfig. It appears to be specific to the -ftrivial-auto-var-init=pattern option. Reduced test case attached, extracted from https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/spi/spi-stm32-qspi.c#n519 e.g. gcc -v -O2 -ftrivial-auto-var-init=pattern -Werror=uninitialized -c qspi.i -o /dev/null Using built-in specs. COLLECT_GCC=gcc Target: x86_64-pc-linux-gnu Configured with: /var/tmp/portage/sys-devel/gcc-12.2.1_p20221231/work/gcc-12-20221231/configure --host=x86_64-pc-linux-gnu --build=x86_64-pc-linux-gnu --prefix=/usr --bindir=/usr/x86_64-pc-linux-gnu/gcc-bin/12 --includedir=/usr/lib/gcc/x86_64-pc-linux-gnu/12/include --datadir=/usr/share/gcc-data/x86_64-pc-linux-gnu/12 --mandir=/usr/share/gcc-data/x86_64-pc-linux-gnu/12/man --infodir=/usr/share/gcc-data/x86_64-pc-linux-gnu/12/info --with-gxx-include-dir=/usr/lib/gcc/x86_64-pc-linux-gnu/12/include/g++-v12 --with-python-dir=/share/gcc-data/x86_64-pc-linux-gnu/12/python --enable-languages=c,c++,d,go,fortran,ada --enable-obsolete --enable-secureplt --disable-werror --with-system-zlib --enable-nls --without-included-gettext --disable-libunwind-exceptions --enable-checking=release --with-bugurl=https://bugs.gentoo.org/ --with-pkgversion='Gentoo 12.2.1_p20221231 p8' --with-gcc-major-version-only --disable-esp --enable-libstdcxx-time --disable-libstdcxx-pch --enable-shared --enable-threads=posix --enable-__cxa_atexit --enable-clocale=gnu --enable-multilib --with-multilib-list=m32,m64 --disable-fixed-point --enable-targets=all --enable-libgomp --disable-libssp --disable-libada --disable-cet --disable-systemtap --disable-valgrind-annotations --enable-vtable-verify --with-zstd --enable-lto --with-isl --disable-isl-version-check --enable-default-pie --enable-default-ssp --with-build-config=bootstrap-lto Thread model: posix Supported LTO compression algorithms: zlib zstd gcc version 12.2.1 20221231 (Gentoo 12.2.1_p20221231 p8) COLLECT_GCC_OPTIONS='-v' '-O2' '-ftrivial-auto-var-init=pattern' '-Werror=uninitialized' '-c' '-o' '/dev/null' '-mtune=generic' '-march=x86-64' /usr/libexec/gcc/x86_64-pc-linux-gnu/12/cc1 -fpreprocessed qspi.i -quiet -dumpbase qspi.i -dumpbase-ext .i -mtune=generic -march=x86-64 -O2 -Werror=uninitialized -version -ftrivial-auto-var-init=pattern -o /tmp/ccMHYckL.s GNU C17 (Gentoo 12.2.1_p20221231 p8) version 12.2.1 20221231 (x86_64-pc-linux-gnu) compiled by GNU C version 12.2.1 20221231, GMP version 6.2.1, MPFR version 4.2.0, MPC version 1.3.1, isl version isl-0.24-GMP GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072 GNU C17 (Gentoo 12.2.1_p20221231 p8) version 12.2.1 20221231 (x86_64-pc-linux-gnu) compiled by GNU C version 12.2.1 20221231, GMP version 6.2.1, MPFR version 4.2.0, MPC version 1.3.1, isl version isl-0.24-GMP GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072 Compiler executable checksum: 0fe3c6b2f620dfca480d344f2a96d9ed qspi.i: In function ‘stm32_qspi_dirmap_read’: qspi.i:40:20: error: ‘op’ is used uninitialized [-Werror=uninitialized] 40 | struct spi_mem_op op; |^~ qspi.i:40:20: note: ‘op’ declared here 40 | struct spi_mem_op op; |^~ cc1: some warnings being treated as errors -fanalyzer additionally reports: qspi.i: In function ‘stm32_qspi_dirmap_read’: qspi.i:40:20: warning: use of uninitialized value ‘*(long int *)((char *)&op + offsetof(struct spi_mem_op, addr.nbytes))’ [CWE-457] [-Wanalyzer-use-of-uninitialized-value] 40 | struct spi_mem_op op; |^~ ‘stm32_qspi_dirmap_read’: events 1-2 | | 40 | struct spi_mem_op op; | |^~ | || | |(1) region created on stack here | |(2) use of uninitialized value ‘*(long int *)((char *)&op + offsetof(struct spi_mem_op, addr.nbytes))’ here | qspi.i:40:20: warning: use of uninitialized value ‘*(long int *)((char *)&op + offsetof(struct spi_mem_op, dummy.nbytes))’ [CWE-457] [-Wanalyzer-use-of-uninitialized-value] 40 | struct spi_m
[Bug tree-optimization/108402] False positive Wuninitialized with ftrivial-auto-var-init=pattern
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108402 pefoley2 at pefoley dot com changed: What|Removed |Added Attachment #54271|0 |1 is obsolete|| --- Comment #3 from pefoley2 at pefoley dot com --- Created attachment 54275 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=54275&action=edit Partially reduced testcase Testcase reduced via creduce/delta to the point that it fits in the attachment size.
[Bug tree-optimization/108402] False positive Wuninitialized with ftrivial-auto-var-init=pattern
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108402 --- Comment #4 from pefoley2 at pefoley dot com --- Yeah, I had a lot of trouble getting creduce to do something sane with the testcase that didn't wind up just deleting everything. I wound up trying delta, which got me a smaller, but still enormous repo. It should also be reproducible via make O=um ARCH=um allyesconfig drivers/spi/spi-stm32-qspi.o in a 6.1 linux kernel tree.
[Bug tree-optimization/108402] False positive Wuninitialized with ftrivial-auto-var-init=pattern
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108402 --- Comment #6 from pefoley2 at pefoley dot com --- The attached file repos the issue for me. I avoided trying to compress it per https://gcc.gnu.org/bugs/ "An attached archive (tar, zip, shar, whatever) containing all (or some) of the above." being listed under "What we do not want". And yeah, the steps to repo from a kernel checkout were added mostly for completeness, I didn't expect people to need to use them.
[Bug middle-end/80922] #pragma diagnostic ignored not honoured with -flto
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80922 pefoley2 at pefoley dot com changed: What|Removed |Added CC||pefoley2 at pefoley dot com --- Comment #8 from pefoley2 at pefoley dot com --- Note that this appears to be affecting the gcc source tree. Attempting a build with --with-build-config=bootstrap-lto --enable-werror errors out with: In function ‘release’, inlined from ‘release’ at ../../gcc/vec.h:1915:0, inlined from ‘__dt_base ’ at ../../gcc/vec.h:1574:0, inlined from ‘visit_reference_op_call.isra’ at ../../gcc/tree-ssa-sccvn.cc:5562:0: ../../gcc/vec.h:316: error: ‘free’ called on unallocated object ‘accesses’ [-Werror=free-nonheap-object] 316 | ::free (v); | ../../gcc/tree-ssa-sccvn.cc: In function ‘visit_reference_op_call.isra’: ../../gcc/tree-ssa-sccvn.cc:5457: note: declared here 5457 | auto_vec accesses; | lto1: all warnings being treated as errors Due to this pragma being ignored: https://gcc.gnu.org/git/?p=gcc.git;a=blob;f=gcc/vec.h;h=a536b68732ddcb9ed7b223803308b3e079a53969;hb=HEAD#l300
[Bug middle-end/80922] #pragma diagnostic ignored not honoured with -flto
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80922 --- Comment #10 from pefoley2 at pefoley dot com --- It does? I wasn't aware of that. My read of the configure options is that the two options are tangential. And from a quick skim, I couldn't find anything that made enabling lto suppress Werror. Besides, regardless of whether it's supported or not, it's another example of this issue in the wild.
