------- Comment #1 from tbm at cyrius dot com 2007-10-21 09:46 -------
The problem is that gcc-4.2 generates a bne instruction that references a
label that doesn't exist. This happens with -O1 or higher. It doesn't
happen with gcc 4.1 or current trunk.
If you compile the attached preprocessed source and look at the assembler
code you'll see it. Search for L2043 when you compile with -O1, for
L2120 with -O2.
% gcc-4.2 -c -S -O1 erlang-beam_emu.i
Looking at erlang-beam_emu.s, we get
$L2042:
sw $0,44($sp)
sw $19,0($21)
sw $20,4($21)
lw $25,%got(save_reg.15912)($28)
nop
sw $23,%lo(save_reg.15912)($25)
lw $22,60($21)
nop
lw $2,0($22)
lw $3,%got($L2035)($28)
nop
addiu $3,$3,%lo($L2035)
bne $2,$3,$L2043
nop
addiu $2,$20,8
beq $2,$0,$L2049
move $17,$0
$L2637:
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33848
