https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89401
Bug ID: 89401
Summary: The generated object file does not automatically
relocate the address using the cl link
Product: gcc
Version: 8.1.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: rdmsr at protonmail dot com
Target Milestone: ---
__asm__ (
"push rbp;\n\t"
"jmp Label;\n\t"
"mov rbp,offset cs:Label;\n\t"
"mov rbp,offset Label;\n\t"
"mov rbp,Label;\n\t"
"mov rbp,Label;\n\t"
"mov rbp,cs:Label;\n\t"
"lea rbp,Label;\n\t"
"Label:\n\t"
"push rbp;\n\t"
);
I want to use GCC inline assembly to get the Label address.
Use the following command to get the object file:
gcc64 -c -s -masm=intel 1.cpp
Now I get the file 1.o
I used a disassembler to view assembly instructions：
.text:0000000000000000 push rbp
.text:0000000000000001 jmp short loc_32
.text:0000000000000003 ;
---------------------------------------------------------------------------
.text:0000000000000003 mov rbp, 32h
.text:000000000000000A mov rbp, 32h
.text:0000000000000011 mov rbp, qword ptr ds:loc_32
.text:0000000000000019 mov rbp, qword ptr ds:loc_32
.text:0000000000000021 db 2Eh
.text:0000000000000021 mov rbp, qword ptr loc_32
.text:000000000000002A lea rbp, ds:32h
.text:0000000000000032
.text:0000000000000032 loc_32: ; CODE XREF:
test+1↑j
.text:0000000000000032 ; DATA XREF:
test+11↑r ...
.text:0000000000000032 push rbp
.text:0000000000000033 mov eax, 0
.text:0000000000000038 retn
I need to link this file with vc++：
Then use the disassembler to see the pe file with the link succeeded：
.text:0000000140011820 sub_140011820 proc near ; CODE XREF:
sub_140011307↑j
.text:0000000140011820 push rbp
.text:0000000140011821 jmp short loc_140011852
.text:0000000140011823 ;
---------------------------------------------------------------------------
.text:0000000140011823 mov rbp, 32h
.text:000000014001182A mov rbp, 32h
.text:0000000140011831 mov rbp, ds:32h
.text:0000000140011839 mov rbp, ds:32h
.text:0000000140011841 db 2Eh
.text:0000000140011841 mov rbp, cs:32h
.text:000000014001184A lea rbp, ds:32h
.text:0000000140011852
.text:0000000140011852 loc_140011852: ; CODE XREF:
sub_140011820+1↑j
.text:0000000140011852 push rbp
.text:0000000140011853 mov eax, 0
.text:0000000140011858 retn
As you see now, he doesn't seem to relocate the address.
When I used nasm to generate object files it did it。
I don't know if it's a bug or a feature missing, just report it now.
