consider the following code snippet 
 
-------- nan.cc ------- 
#include <iostream> 
int main() { 
        double x = 0.55555555555555558023; 
        std::cout << x << " "; 
        std::cout << x << " "; 
        std::cout << std::endl; 
        return 0; 
} 
-------- nan.cc ------- 
 
> g++-4.0-20041226 -v 
Using built-in specs. 
Configured with: ../gcc-4.0-20041226/configure --prefix=/opt/gcc-4.0-20041226 
--enable-shared --enable-languages=c,c++ --enable-threads=posix 
--enable-__cxa_atexit --enable-clocale=gnu --disable-nls 
--program-suffix=-4.0-20041226 --with-arch=pentium3 --disable-checking 
Thread model: posix 
gcc version 4.0.0 20041226 (experimental) 
 
> g++-4.0-20041226 nan.cc 
> ldd a.out 
       libstdc++.so.6 => /opt/gcc-4.0-20041226/lib/libstdc++.so.6 (0x40017000) 
       libm.so.6 => /lib/libm.so.6 (0x400fc000) 
       libgcc_s.so.1 => /opt/gcc-4.0-20041226/lib/libgcc_s.so.1 (0x4011f000) 
       libc.so.6 => /lib/libc.so.6 (0x40129000) 
       /lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x40000000) 
> ./a.out 
0.555556 nan 
 
well this nan shouldn't be there 
 
> g++-4.0-20041226 nan.cc -static 
 
> ./a.out 
0.555556 0.555556 
 
> g++-4.0-20041212 -v 
Reading specs from /opt/gcc-4.0-20041212/lib/gcc/i686-pc-linux-gnu/4.0.0/specs 
Configured with: ../gcc-4.0-20041212/configure --prefix=/opt/gcc-4.0-20041212 
--enable-shared --enable-languages=c,c++ --enable-threads=posix 
--enable-__cxa_atexit --enable-clocale=gnu --disable-nls 
--program-suffix=-4.0-20041212 --with-arch=pentium3 --disable-checking 
Thread model: posix 
gcc version 4.0.0 20041212 (experimental) 
 
> g++-4.0-20041212 nan.cc 
> ldd ./a.out 
       libstdc++.so.6 => /opt/gcc-4.0-20041212/lib/libstdc++.so.6 (0x40017000) 
       libm.so.6 => /lib/libm.so.6 (0x400fb000) 
       libgcc_s.so.1 => /opt/gcc-4.0-20041212/lib/libgcc_s.so.1 (0x4011e000) 
       libc.so.6 => /lib/libc.so.6 (0x40128000) 
       /lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x40000000) 
 
> ./a.out 
0.555556 0.555556 
 
g++-4.0-20041212 doesn't have this problem

-- 
           Summary: wrong code regression or library problem in gcc-4.0-
                    20041226
           Product: gcc
           Version: 4.0.0
            Status: UNCONFIRMED
          Severity: critical
          Priority: P2
         Component: regression
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: andre dot maute at gmx dot de
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19174

Reply via email to