------- Comment #3 from cepeda at gmail dot com 2009-10-16 16:51 -------
This bug has no changed for months, I think it is still active.
It seems not to work only when size of char[] is 3 (2+'\0'). A test case is
this:
// Begin of code
#include <stdio.h>
#include <string.h>
int main(int argc, char **argv)
{
printf("%d",strcmp(argv[0],"A")); // NO warning
printf("%d",strcmp(argv[0],"AA")); // warning: array subscript
printf("%d",strcmp(argv[0],"AAA")); // NO warning
return 0;
}
// End of code
The compilation says:
$ gcc -v -save-temps -O3 -fno-builtin -funsigned-char -Wall test.c
Using built-in specs.
Target: i486-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Ubuntu 4.4.1-4ubuntu8'
--with-bugurl=file:///usr/share/doc/gcc-4.4/README.Bugs
--enable-languages=c,c++,fortran,objc,obj-c++ --prefix=/usr --enable-shared
--enable-multiarch --enable-linker-build-id --with-system-zlib
--libexecdir=/usr/lib --without-included-gettext --enable-threads=posix
--with-gxx-include-dir=/usr/include/c++/4.4 --program-suffix=-4.4 --enable-nls
--enable-clocale=gnu --enable-libstdcxx-debug --enable-objc-gc
--enable-targets=all --disable-werror --with-arch-32=i486 --with-tune=generic
--enable-checking=release --build=i486-linux-gnu --host=i486-linux-gnu
--target=i486-linux-gnu
Thread model: posix
gcc version 4.4.1 (Ubuntu 4.4.1-4ubuntu8)
COLLECT_GCC_OPTIONS='-v' '-save-temps' '-O3' '-fno-builtin' '-funsigned-char'
'-Wall' '-mtune=generic' '-march=i486'
/usr/lib/gcc/i486-linux-gnu/4.4.1/cc1 -E -quiet -v test.c -D_FORTIFY_SOURCE=2
-mtune=generic -march=i486 -Wall -fno-builtin -funsigned-char -O3
-fpch-preprocess -fstack-protector -o test.i
ignoring nonexistent directory "/usr/local/include/i486-linux-gnu"
ignoring nonexistent directory
"/usr/lib/gcc/i486-linux-gnu/4.4.1/../../../../i486-linux-gnu/include"
ignoring nonexistent directory "/usr/include/i486-linux-gnu"
#include "..." search starts here:
#include <...> search starts here:
/usr/local/include
/usr/lib/gcc/i486-linux-gnu/4.4.1/include
/usr/lib/gcc/i486-linux-gnu/4.4.1/include-fixed
/usr/include
End of search list.
COLLECT_GCC_OPTIONS='-v' '-save-temps' '-O3' '-fno-builtin' '-funsigned-char'
'-Wall' '-mtune=generic' '-march=i486'
/usr/lib/gcc/i486-linux-gnu/4.4.1/cc1 -fpreprocessed test.i -quiet -dumpbase
test.c -mtune=generic -march=i486 -auxbase test -O3 -Wall -version -fno-builtin
-funsigned-char -fstack-protector -o test.s
GNU C (Ubuntu 4.4.1-4ubuntu8) version 4.4.1 (i486-linux-gnu)
compiled by GNU C version 4.4.1, GMP version 4.3.1, MPFR version
2.4.1-p2.
GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
Compiler executable checksum: 293503c4ddf766b61fc5ff6a5ff38cdc
test.c: In function main:
test.c:7: warning: array subscript is above array bounds
COLLECT_GCC_OPTIONS='-v' '-save-temps' '-O3' '-fno-builtin' '-funsigned-char'
'-Wall' '-mtune=generic' '-march=i486'
as -V -Qy -o test.o test.s
GNU assembler version 2.19.92 (i486-linux-gnu) using BFD version (GNU Binutils
for Ubuntu) 2.19.92.20091014
COMPILER_PATH=/usr/lib/gcc/i486-linux-gnu/4.4.1/:/usr/lib/gcc/i486-linux-gnu/4.4.1/:/usr/lib/gcc/i486-linux-gnu/:/usr/lib/gcc/i486-linux-gnu/4.4.1/:/usr/lib/gcc/i486-linux-gnu/:/usr/lib/gcc/i486-linux-gnu/4.4.1/:/usr/lib/gcc/i486-linux-gnu/
LIBRARY_PATH=/usr/lib/gcc/i486-linux-gnu/4.4.1/:/usr/lib/gcc/i486-linux-gnu/4.4.1/:/usr/lib/gcc/i486-linux-gnu/4.4.1/../../../../lib/:/lib/../lib/:/usr/lib/../lib/:/usr/lib/gcc/i486-linux-gnu/4.4.1/../../../:/lib/:/usr/lib/:/usr/lib/i486-linux-gnu/
COLLECT_GCC_OPTIONS='-v' '-save-temps' '-O3' '-fno-builtin' '-funsigned-char'
'-Wall' '-mtune=generic' '-march=i486'
/usr/lib/gcc/i486-linux-gnu/4.4.1/collect2 --build-id --eh-frame-hdr -m
elf_i386 --hash-style=both -dynamic-linker /lib/ld-linux.so.2 -z relro
/usr/lib/gcc/i486-linux-gnu/4.4.1/../../../../lib/crt1.o
/usr/lib/gcc/i486-linux-gnu/4.4.1/../../../../lib/crti.o
/usr/lib/gcc/i486-linux-gnu/4.4.1/crtbegin.o
-L/usr/lib/gcc/i486-linux-gnu/4.4.1 -L/usr/lib/gcc/i486-linux-gnu/4.4.1
-L/usr/lib/gcc/i486-linux-gnu/4.4.1/../../../../lib -L/lib/../lib
-L/usr/lib/../lib -L/usr/lib/gcc/i486-linux-gnu/4.4.1/../../..
-L/usr/lib/i486-linux-gnu test.o -lgcc --as-needed -lgcc_s --no-as-needed -lc
-lgcc --as-needed -lgcc_s --no-as-needed
/usr/lib/gcc/i486-linux-gnu/4.4.1/crtend.o
/usr/lib/gcc/i486-linux-gnu/4.4.1/../../../../lib/crtn.o
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35903
