gcc generates incorrect code for static members in some cases. Consider the following code:
struct C { static __thread int x; static __thread int y; }; __thread int C::x; void g() { int z = C::x; z = C::y; } When this is compiled on an x86 machine with gcc -S, the body of g() is translated as: movl %gs:[EMAIL PROTECTED], %eax movl %eax, -4(%ebp) movl _ZN1C1yE, %eax movl %eax, -4(%ebp) note that C::x is accessed using an offset from the thread pointer, which is correct. C::y, however, is accessed as if it were an ordinary (not thread-local) static member, which is incorrect. I have also observed this problem on ia64 machines, so it seems to be a general issue. These are similar to the symptoms described in bug 13668, although that was determined to be a glibc issue. I see no way in which glibc could be involved here. Environment: System: Linux algol.uwaterloo.ca 2.6.8-1-k7 #1 Thu Nov 25 04:13:37 UTC 2004 i686 GNU/Linux Architecture: i686 host: i486-pc-linux-gnu build: i486-pc-linux-gnu target: i486-pc-linux-gnu configured with: ../gcc/configure -v --enable-languages=c,c++ --prefix=/u/rcbilson/software/gcc --enable-shared --with-system-zlib --enable-nls --without-included-gettext --enable-__cxa_atexit --enable-clocale=gnu --enable-debug i486-linux How-To-Repeat: Compile the above code fragment using gcc -S. -- Summary: __thread static class members Product: gcc Version: 4.0.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: rcbilson at plg dot uwaterloo dot ca CC: gcc-bugs at gcc dot gnu dot org GCC build triplet: i486-pc-linux-gnu GCC host triplet: i486-pc-linux-gnu GCC target triplet: i486-pc-linux-gnu http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19450