Compiling the test case in the attached patch using arm-linux-gnueabi 
target g++ with the options "-O2 -fweb -fPIC -fvisibility=hidden" will 
give an error:

Assembler messages:
Error: symbol `.LPIC0' is already defined

That's because an instruction, which can't be copied, is combined into 
another instruction while that non-copyable instruction is still kept 
since its result is needed later. GCC will generate the same label 
".LPIC0" for that non-copyable instruction and the combined instruction 
since the label number is also copied and same for both instructions.

With this patch, GCC will not combine instructions if they can't be 
copied. Tested on arm-linux-gnueabi with c,c++,lto. No regressions are 
found.

Is it OK?


Regards,
-- 
Jie Zhang
CodeSourcery