http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53831
Richard Guenther <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |rafael.espindola at gmail
| |dot com
Known to fail| |4.8.0
--- Comment #7 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-07-03
12:39:46 UTC ---
Heh, not sure ;) Btw, the issue reproduces on trunk as well. And if I use
-fno-fat-lto-objects I get a maybe more easily to debug linker failure:
repro> make USE_LTO=1
/space/rguenther/install/gcc-4.7.1/bin/g++ -B /abuild/rguenther/trunk-g/gcc -c
main.cpp -o main.o -ffunction-sections -funwind-tables -O2 -DNDEBUG
-fno-exceptions -fno-rtti -fno-fat-lto-objects -flto
In file included from main.cpp:1:0:
common.h:8:22: warning: inline function 'virtual void C::f()' used but never
defined [enabled by default]
inline virtual void f();
^
/space/rguenther/install/gcc-4.7.1/bin/g++ -B /abuild/rguenther/trunk-g/gcc -c
impl.cpp -o impl.o -ffunction-sections -funwind-tables -O2 -DNDEBUG
-fno-exceptions -fno-rtti -fno-fat-lto-objects -flto
ar rcs libdummy.a impl.o
/space/rguenther/install/gcc-4.7.1/bin/g++ -B /abuild/rguenther/trunk-g/gcc
main.o libdummy.a -o test.exe -flto
/tmp/ccXwNVS0.ltrans0.ltrans.o: In function `main':
ccXwNVS0.ltrans0.o:(.text+0xc): undefined reference to `vtable for C'
ccXwNVS0.ltrans0.o:(.text+0x18): undefined reference to `C::f()'
ccXwNVS0.ltrans0.o:(.text+0x24): undefined reference to `C::g()'
collect2: error: ld returned 1 exit status
make: *** [test.exe] Error 1
note the warning about C::f() being never defined. That leaves the vtable
for C in main.o with a reference to an external function - not sure if
that's valid from the ABI point of view (or if this is valid C++).
Might also be related to PR53808.
