Bug in 6.x' C++ compiler

[Kostik Belousov]

On Wed, Oct 11, 2006 at 01:22:57PM -0400, Mikhail Teterin wrote:
> GCC would not fix the bug described in
> 
> 	http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29390
> 
> because the compiler is of an unsupported version (they only support 4.x now).
> 
> Yet, the problem is rather real and hits when the devel/icu port is
> built with low optimization (-O1 or -O0).
>
> Any chance, someone with interest in GCC internals and FreeBSD can
> find the fix?
>
> Simply compiling the loctest.ii, that is attached to the above bugzilla 
> report, is enough to reproduce the problem. Compiling with `-march=pentium4' 
> triggers the bug -- a bogus symbol is inserted:
> 
> 	% c++ -O0 -g -c  -pipe -march=pentium4 loctest.ii
> 	% nm locate.o | fgrep .LC
> 	U .LC786
> 
> Compiling without the -march (or with -O2) does not insert the bogus symbol:
> 
> 	% c++ -O2 -g -c -pipe -march=pentium4 loctest.ii
> 	% nm loctest.o | fgrep .LC
> 	% c++ -O0 -g -c -pipe loctest.ii
> 	% nm loctest.o | fgrep .LC
> 	%
> 
> I'm seeing this with both 3.4.4 and 3.4.6 versions of GCC... Thanks!
> 
> 	-mi
deviant% /usr/local/opt/gcc-3.4.6/bin/g++ -O0 -g -c -fno-strict-aliasing -pipe -march=pentium4 loctest.ii
deviant% nm loctest.o | grep LC
         U _ZNK7icu_3_66Locale7getLCIDEv
deviant% c++ -O0 -g -c -fno-strict-aliasing -pipe -march=pentium4 loctest.ii
deviant% nm loctest.o | grep LC
         U .LC786
         U _ZNK7icu_3_66Locale7getLCIDEv
deviant% /usr/local/opt/gcc-3.4.6/bin/g++ -v 
Reading specs from /usr/local/opt/gcc-3.4.6/lib/gcc/i386-little-freebsd6/3.4.6/specs
Configured with: ../gcc-3.4.6/configure --prefix=/usr/local/opt/gcc-3.4.6 --enable-shared --enable-threads --with-system-zlib --enable-__cxa_atexit --disable-nls --enable-long-long --with-as=/usr/local/opt/binutils/bin/as --with-ld=/usr/local/opt/binutils/bin/ld --enable-languages=c,c++,f77,objc,ada,java --host=i386-little-freebsd6
Thread model: posix
gcc version 3.4.6
deviant% c++ -v
Using built-in specs.
Configured with: FreeBSD/i386 system compiler
Thread model: posix
gcc version 3.4.6 [FreeBSD] 20060305

opt/gcc-3.4.6 is the stock version of the 3.4.6 built directly from the FSF
sources (relatively long time ago).
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