MIPS Wrong-code regression.

Wed Jan 31 07:41:00 GMT 2007

David Daney <ddaney@avtrex.com> writes:
> Sometime between 1/7 and 1/16 on the trunk I started getting wrong code 
> on a bunch of java testcases under mipsel-linux.
>> It looks related to (but not necessarily caused by) this patch:
>> http://gcc.gnu.org/ml/gcc-patches/2006-03/msg01346.html
>> For example if we examine the assembler output of the PR9577.java 
> testcase, we see:
>> .
> .
> .
> $LBB2:
> lw 2,40ドル($fp)
> sw 2,24ドル($fp)
> lw 2,24ドル($fp)
> move 4,ドル2ドル
> .option pic0
> jal _ZN4java4lang6ObjectC1Ev
> nop
>> .option pic2
> lw 28,16ドル($fp)
> $LBE2:
> move $sp,$fp
> lw 31,36ドル($sp)
> lw $fp,32($sp)
> addiu $sp,$sp,40
> j 31ドル
> nop
>> The call to _ZN4java4lang6ObjectC1Ev is being generated as non-pic, even 
> though that symbol is defined in libgcj.so. The assembler and linker 
> conspire to jump to address 0x00000000 for this call.
>> It looks like the logic that decides if a symbol is external to the 
> compilation unit is faulty.
>> Any ideas about where it might have gone wrong?

Not off-hand. I think -mno-shared is using the right interfaces to
test for locality.
> I will try to look into it more tomorrow.

Thanks, let me know how it goes. I won't have any time to do
out-of-hours gcc stuff today, but might tomorrow night.
Richard