https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66232
Bug ID: 66232
Summary: -fPIC -fno-plt -mx32 fails to generate indirect branch
via GOT
Product: gcc
Version: 6.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: hjl.tools at gmail dot com
CC: ubizjak at gmail dot com
Target Milestone: ---
Target: x86_64-pc-linux-gnu
[hjl@gnu-tools-1 plt-1]$ cat x.i
extern void bar (void);
void
foo (void)
{
bar ();
}
[hjl@gnu-tools-1 plt-1]$ make
/export/build/gnu/gcc-x32/build-x86_64-linux/gcc/xgcc
-B/export/build/gnu/gcc-x32/build-x86_64-linux/gcc/ -O2 -fPIC -fno-plt -mx32 -S
x.i
[hjl@gnu-tools-1 plt-1]$ cat x.s
.file "x.i"
.section .text.unlikely,"ax",@progbits
.LCOLDB0:
.text
.LHOTB0:
.p2align 4,,15
.globl foo
.type foo, @function
foo:
.LFB0:
.cfi_startproc
movl bar@GOTPCREL(%rip), %eax
jmp *%rax
.cfi_endproc
.LFE0:
.size foo, .-foo
.section .text.unlikely
.LCOLDE0:
.text
.LHOTE0:
.ident "GCC: (GNU) 6.0.0 20150521 (experimental)"
.section .note.GNU-stack,"",@progbits
[hjl@gnu-tools-1 plt-1]$
We should generate
jmp *bar@GOTPCREL(%rip)
since GOT slot is 64-bit.
