https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107566
Bug ID: 107566
Summary: array out of bounds not detected
Product: gcc
Version: 13.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: analyzer
Assignee: dmalcolm at gcc dot gnu.org
Reporter: jamie.bainbridge at gmail dot com
Target Milestone: ---
Minimal reproducer:
int main(void)
{
int my_array[3] = { 0 };
for(int i = 0; i < 6; i++)
my_array[i] = i;
return 0;
}
The array has 3 members, but the loop counts further.
This is caught by cppcheck, clang alpha, and PVS-Studio, but not gcc trunk.
URL to reproducer: https://godbolt.org/z/dx96qbcqs
Commandline options: -O0 -Wall -Wextra -Wpedantic -fanalyzer -v
Tested version: gcc
(Compiler-Explorer-Build-gcc-c56826d0f3b143a9cb64ee263707046f8073c1b6-binutils-2.38)
13.0.0 20221106 (experimental)
Complete verbose output:
Using built-in specs.
COLLECT_GCC=/opt/compiler-explorer/gcc-snapshot/bin/gcc
Target: x86_64-linux-gnu
Configured with: ../gcc-trunk-20221107/configure
--prefix=/opt/compiler-explorer/gcc-build/staging --build=x86_64-linux-gnu
--host=x86_64-linux-gnu --target=x86_64-linux-gnu --disable-bootstrap
--enable-multiarch --with-abi=m64 --with-multilib-list=m32,m64,mx32
--enable-multilib --enable-clocale=gnu
--enable-languages=c,c++,fortran,ada,objc,obj-c++,d --enable-ld=yes
--enable-gold=yes --enable-libstdcxx-debug --enable-libstdcxx-time=yes
--enable-linker-build-id --enable-lto --enable-plugins --enable-threads=posix
--with-pkgversion=Compiler-Explorer-Build-gcc-c56826d0f3b143a9cb64ee263707046f8073c1b6-binutils-2.38
--enable-libstdcxx-backtrace=yes
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 13.0.0 20221106 (experimental)
(Compiler-Explorer-Build-gcc-c56826d0f3b143a9cb64ee263707046f8073c1b6-binutils-2.38)
COLLECT_GCC_OPTIONS='-fdiagnostics-color=always' '-g' '-o' '/app/output.s'
'-masm=intel' '-S' '-O0' '-Wall' '-Wextra' '-Wpedantic' '-fanalyzer' '-v'
'-save-temps' '-mtune=generic' '-march=x86-64' '-dumpdir' '/app/'
/opt/compiler-explorer/gcc-trunk-20221107/bin/../libexec/gcc/x86_64-linux-gnu/13.0.0/cc1
-E -quiet -v -imultiarch x86_64-linux-gnu -iprefix
/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/x86_64-linux-gnu/13.0.0/
<source> -masm=intel -mtune=generic -march=x86-64 -Wall -Wextra -Wpedantic
-fdiagnostics-color=always -fanalyzer -g -fworking-directory -O0
-fpch-preprocess -o /app/output.i
ignoring nonexistent directory
"/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/x86_64-linux-gnu/13.0.0/../../../../x86_64-linux-gnu/include"
ignoring duplicate directory
"/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/../../lib/gcc/x86_64-linux-gnu/13.0.0/include"
ignoring nonexistent directory "/usr/local/include/x86_64-linux-gnu"
ignoring duplicate directory
"/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/../../lib/gcc/x86_64-linux-gnu/13.0.0/include-fixed/x86_64-linux-gnu"
ignoring duplicate directory
"/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/../../lib/gcc/x86_64-linux-gnu/13.0.0/include-fixed"
ignoring nonexistent directory
"/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/../../lib/gcc/x86_64-linux-gnu/13.0.0/../../../../x86_64-linux-gnu/include"
#include "..." search starts here:
#include <...> search starts here:
/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/x86_64-linux-gnu/13.0.0/include
/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/x86_64-linux-gnu/13.0.0/include-fixed/x86_64-linux-gnu
/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/x86_64-linux-gnu/13.0.0/include-fixed
/usr/local/include
/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/../../include
/usr/include/x86_64-linux-gnu
/usr/include
End of search list.
COLLECT_GCC_OPTIONS='-fdiagnostics-color=always' '-g' '-o' '/app/output.s'
'-masm=intel' '-S' '-O0' '-Wall' '-Wextra' '-Wpedantic' '-fanalyzer' '-v'
'-save-temps' '-mtune=generic' '-march=x86-64' '-dumpdir' '/app/'
/opt/compiler-explorer/gcc-trunk-20221107/bin/../libexec/gcc/x86_64-linux-gnu/13.0.0/cc1
-fpreprocessed /app/output.i -quiet -dumpdir /app/ -dumpbase output.c
-dumpbase-ext .c -masm=intel -mtune=generic -march=x86-64 -g -O0 -Wall -Wextra
-Wpedantic -version -fdiagnostics-color=always -fanalyzer -o /app/output.s
GNU C17
(Compiler-Explorer-Build-gcc-c56826d0f3b143a9cb64ee263707046f8073c1b6-binutils-2.38)
version 13.0.0 20221106 (experimental) (x86_64-linux-gnu)
compiled by GNU C version 9.4.0, GMP version 6.2.1, MPFR version 4.1.0,
MPC version 1.2.1, isl version isl-0.24-GMP
GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
GNU C17
(Compiler-Explorer-Build-gcc-c56826d0f3b143a9cb64ee263707046f8073c1b6-binutils-2.38)
version 13.0.0 20221106 (experimental) (x86_64-linux-gnu)
compiled by GNU C version 9.4.0, GMP version 6.2.1, MPFR version 4.1.0,
MPC version 1.2.1, isl version isl-0.24-GMP
GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
Compiler executable checksum: 0290f59709883f52562bc4105777b706
<source>: In function 'main':
<source>:3:13: warning: variable 'my_array' set but not used
[-Wunused-but-set-variable]
3 | int my_array[3] = { 0 };
| ^~~~~~~~
COMPILER_PATH=/opt/compiler-explorer/gcc-trunk-20221107/bin/../libexec/gcc/x86_64-linux-gnu/13.0.0/:/opt/compiler-explorer/gcc-trunk-20221107/bin/../libexec/gcc/x86_64-linux-gnu/:/opt/compiler-explorer/gcc-trunk-20221107/bin/../libexec/gcc/:/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/x86_64-linux-gnu/13.0.0/../../../../x86_64-linux-gnu/bin/
LIBRARY_PATH=/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/x86_64-linux-gnu/13.0.0/:/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/x86_64-linux-gnu/:/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/:/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/x86_64-linux-gnu/13.0.0/../../../../lib64/:/lib/x86_64-linux-gnu/:/lib/../lib64/:/usr/lib/x86_64-linux-gnu/:/usr/lib/../lib64/:/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/x86_64-linux-gnu/13.0.0/../../../../x86_64-linux-gnu/lib/:/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/x86_64-linux-gnu/13.0.0/../../../:/lib/:/usr/lib/
COLLECT_GCC_OPTIONS='-fdiagnostics-color=always' '-g' '-o' '/app/output.s'
'-masm=intel' '-S' '-O0' '-Wall' '-Wextra' '-Wpedantic' '-fanalyzer' '-v'
'-save-temps' '-mtune=generic' '-march=x86-64' '-dumpdir' '/app/output.'
ASM generation compiler returned: 0
Using built-in specs.
COLLECT_GCC=/opt/compiler-explorer/gcc-snapshot/bin/gcc
COLLECT_LTO_WRAPPER=/opt/compiler-explorer/gcc-trunk-20221107/bin/../libexec/gcc/x86_64-linux-gnu/13.0.0/lto-wrapper
Target: x86_64-linux-gnu
Configured with: ../gcc-trunk-20221107/configure
--prefix=/opt/compiler-explorer/gcc-build/staging --build=x86_64-linux-gnu
--host=x86_64-linux-gnu --target=x86_64-linux-gnu --disable-bootstrap
--enable-multiarch --with-abi=m64 --with-multilib-list=m32,m64,mx32
--enable-multilib --enable-clocale=gnu
--enable-languages=c,c++,fortran,ada,objc,obj-c++,d --enable-ld=yes
--enable-gold=yes --enable-libstdcxx-debug --enable-libstdcxx-time=yes
--enable-linker-build-id --enable-lto --enable-plugins --enable-threads=posix
--with-pkgversion=Compiler-Explorer-Build-gcc-c56826d0f3b143a9cb64ee263707046f8073c1b6-binutils-2.38
--enable-libstdcxx-backtrace=yes
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 13.0.0 20221106 (experimental)
(Compiler-Explorer-Build-gcc-c56826d0f3b143a9cb64ee263707046f8073c1b6-binutils-2.38)
COLLECT_GCC_OPTIONS='-fdiagnostics-color=always' '-g' '-o' '/app/output.s'
'-O0' '-Wall' '-Wextra' '-Wpedantic' '-fanalyzer' '-v' '-save-temps' '-L.'
'-mtune=generic' '-march=x86-64' '-dumpdir' '/app/output.s-'
/opt/compiler-explorer/gcc-trunk-20221107/bin/../libexec/gcc/x86_64-linux-gnu/13.0.0/cc1
-E -quiet -v -imultiarch x86_64-linux-gnu -iprefix
/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/x86_64-linux-gnu/13.0.0/
<source> -mtune=generic -march=x86-64 -Wall -Wextra -Wpedantic
-fdiagnostics-color=always -fanalyzer -g -fworking-directory -O0
-fpch-preprocess -o /app/output.s-example.i
ignoring nonexistent directory
"/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/x86_64-linux-gnu/13.0.0/../../../../x86_64-linux-gnu/include"
ignoring duplicate directory
"/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/../../lib/gcc/x86_64-linux-gnu/13.0.0/include"
ignoring nonexistent directory "/usr/local/include/x86_64-linux-gnu"
ignoring duplicate directory
"/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/../../lib/gcc/x86_64-linux-gnu/13.0.0/include-fixed/x86_64-linux-gnu"
ignoring duplicate directory
"/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/../../lib/gcc/x86_64-linux-gnu/13.0.0/include-fixed"
ignoring nonexistent directory
"/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/../../lib/gcc/x86_64-linux-gnu/13.0.0/../../../../x86_64-linux-gnu/include"
#include "..." search starts here:
#include <...> search starts here:
/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/x86_64-linux-gnu/13.0.0/include
/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/x86_64-linux-gnu/13.0.0/include-fixed/x86_64-linux-gnu
/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/x86_64-linux-gnu/13.0.0/include-fixed
/usr/local/include
/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/../../include
/usr/include/x86_64-linux-gnu
/usr/include
End of search list.
COLLECT_GCC_OPTIONS='-fdiagnostics-color=always' '-g' '-o' '/app/output.s'
'-O0' '-Wall' '-Wextra' '-Wpedantic' '-fanalyzer' '-v' '-save-temps' '-L.'
'-mtune=generic' '-march=x86-64' '-dumpdir' '/app/output.s-'
/opt/compiler-explorer/gcc-trunk-20221107/bin/../libexec/gcc/x86_64-linux-gnu/13.0.0/cc1
-fpreprocessed /app/output.s-example.i -quiet -dumpdir /app/output.s- -dumpbase
example.c -dumpbase-ext .c -mtune=generic -march=x86-64 -g -O0 -Wall -Wextra
-Wpedantic -version -fdiagnostics-color=always -fanalyzer -o
/app/output.s-example.s
GNU C17
(Compiler-Explorer-Build-gcc-c56826d0f3b143a9cb64ee263707046f8073c1b6-binutils-2.38)
version 13.0.0 20221106 (experimental) (x86_64-linux-gnu)
compiled by GNU C version 9.4.0, GMP version 6.2.1, MPFR version 4.1.0,
MPC version 1.2.1, isl version isl-0.24-GMP
GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
GNU C17
(Compiler-Explorer-Build-gcc-c56826d0f3b143a9cb64ee263707046f8073c1b6-binutils-2.38)
version 13.0.0 20221106 (experimental) (x86_64-linux-gnu)
compiled by GNU C version 9.4.0, GMP version 6.2.1, MPFR version 4.1.0,
MPC version 1.2.1, isl version isl-0.24-GMP
GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
Compiler executable checksum: 0290f59709883f52562bc4105777b706
<source>: In function 'main':
<source>:3:13: warning: variable 'my_array' set but not used
[-Wunused-but-set-variable]
3 | int my_array[3] = { 0 };
| ^~~~~~~~
COLLECT_GCC_OPTIONS='-fdiagnostics-color=always' '-g' '-o' '/app/output.s'
'-O0' '-Wall' '-Wextra' '-Wpedantic' '-fanalyzer' '-v' '-save-temps' '-L.'
'-mtune=generic' '-march=x86-64' '-dumpdir' '/app/output.s-'
/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/x86_64-linux-gnu/13.0.0/../../../../x86_64-linux-gnu/bin/as
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GNU assembler version 2.38 (x86_64-linux-gnu) using BFD version
(Compiler-Explorer-Build-gcc-c56826d0f3b143a9cb64ee263707046f8073c1b6-binutils-2.38)
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COMPILER_PATH=/opt/compiler-explorer/gcc-trunk-20221107/bin/../libexec/gcc/x86_64-linux-gnu/13.0.0/:/opt/compiler-explorer/gcc-trunk-20221107/bin/../libexec/gcc/x86_64-linux-gnu/:/opt/compiler-explorer/gcc-trunk-20221107/bin/../libexec/gcc/:/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/x86_64-linux-gnu/13.0.0/../../../../x86_64-linux-gnu/bin/
LIBRARY_PATH=/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/x86_64-linux-gnu/13.0.0/:/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/x86_64-linux-gnu/:/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/:/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/x86_64-linux-gnu/13.0.0/../../../../lib64/:/lib/x86_64-linux-gnu/:/lib/../lib64/:/usr/lib/x86_64-linux-gnu/:/usr/lib/../lib64/:/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/x86_64-linux-gnu/13.0.0/../../../../x86_64-linux-gnu/lib/:/opt/compiler-explorer/gcc-trunk-20221107/bin/../lib/gcc/x86_64-linux-gnu/13.0.0/../../../:/lib/:/usr/lib/
COLLECT_GCC_OPTIONS='-fdiagnostics-color=always' '-g' '-o' '/app/output.s'
'-O0' '-Wall' '-Wextra' '-Wpedantic' '-fanalyzer' '-v' '-save-temps' '-L.'
'-mtune=generic' '-march=x86-64' '-dumpdir' '/app/output.s.'
/opt/compiler-explorer/gcc-trunk-20221107/bin/../libexec/gcc/x86_64-linux-gnu/13.0.0/collect2
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/opt/compiler-explorer/gcc-trunk-20221107/bin/../libexec/gcc/x86_64-linux-gnu/13.0.0/liblto_plugin.so
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/lib/x86_64-linux-gnu/crtn.o
COLLECT_GCC_OPTIONS='-fdiagnostics-color=always' '-g' '-o' '/app/output.s'
'-O0' '-Wall' '-Wextra' '-Wpedantic' '-fanalyzer' '-v' '-save-temps' '-L.'
'-mtune=generic' '-march=x86-64' '-dumpdir' '/app/output.s.'
Execution build compiler returned: 0
Program returned: 0
