http://sourceware.org/bugzilla/show_bug.cgi?id=14536
--- Comment #1 from Cary Coutant <ccoutant at google dot com> 2012-08-31 21:19:20 UTC --- I think this is related to the discussion here: http://sourceware.org/ml/binutils/2011-03/msg00220.html. -cary On Fri, Aug 31, 2012 at 2:11 PM, hjl.tools at gmail dot com <sourceware-bugzi...@sourceware.org> wrote: > http://sourceware.org/bugzilla/show_bug.cgi?id=14536 > > Bug #: 14536 > Summary: Unnecessary GOT usages > Product: binutils > Version: 2.23 (HEAD) > Status: NEW > Severity: normal > Priority: P2 > Component: gold > AssignedTo: i...@airs.com > ReportedBy: hjl.to...@gmail.com > CC: ccout...@google.com > Classification: Unclassified > > > On Linux/x86, gold gives > [hjl@gnu-6 symbolic-6]$ cat foo.S > .text > .globl foo > .type foo, @function > foo: > ret > .size foo, .-foo > .globl _start > .type _start, @function > _start: > #ifdef __x86_64__ > movq foo@GOTPCREL(%rip), %rax > #else > movl foo@GOT(%ecx), %eax > #endif > .size _start, .-_start > [hjl@gnu-6 symbolic-6]$ cat foo.t > { > global: > _start; > local: > *; > }; > [hjl@gnu-6 symbolic-6]$ make > gcc -m32 -c -o foo.o foo.S > ./ld -m elf_i386 -Bsymbolic -shared -o libfoo.so foo.o > ./ld -m elf_i386 -pie -o pie foo.o > ./ld -m elf_i386 -o static foo.o > ./ld -m elf_i386 -shared -o shared foo.o --version-script foo.t > objdump -dw libfoo.so > > libfoo.so: file format elf32-i386 > > > Disassembly of section .text: > > 0000016c <foo>: > 16c: c3 ret > > 0000016d <_start>: > 16d: 8b 81 fc ff ff ff mov -0x4(%ecx),%eax > objdump -dw pie > > pie: file format elf32-i386 > > > Disassembly of section .text: > > 00000114 <foo>: > 114: c3 ret > > 00000115 <_start>: > 115: 8b 81 fc ff ff ff mov -0x4(%ecx),%eax > objdump -dw static > > static: file format elf32-i386 > > > Disassembly of section .text: > > 08048074 <foo>: > 8048074: c3 ret > > 08048075 <_start>: > 8048075: 8b 81 fc ff ff ff mov -0x4(%ecx),%eax > objdump -dw shared > > shared: file format elf32-i386 > > > Disassembly of section .text: > > 000000f8 <foo>: > f8: c3 ret > > 000000f9 <_start>: > f9: 8b 81 fc ff ff ff mov -0x4(%ecx),%eax > readelf -SW libfoo.so | grep ".got " || true > [ 7] .got PROGBITS 00001204 000204 000004 00 WA 0 0 > 4 > readelf -SW pie | grep ".got " || true > [ 8] .got PROGBITS 000011a4 0001a4 000004 00 WA 0 0 > 4 > readelf -SW static | grep ".got " || true > [ 2] .got PROGBITS 0804907c 00007c 000004 00 WA 0 0 > 4 > readelf -SW shared | grep ".got " || true > [ 7] .got PROGBITS 00001180 000180 000004 00 WA 0 0 > 4 > [hjl@gnu-6 symbolic-6]$ > > bfd linker gave > > [hjl@gnu-6 symbolic-6]$ make LD=./ld.bfd > gcc -m32 -c -o foo.o foo.S > ./ld.bfd -m elf_i386 -Bsymbolic -shared -o libfoo.so foo.o > ./ld.bfd -m elf_i386 -pie -o pie foo.o > ./ld.bfd -m elf_i386 -o static foo.o > ./ld.bfd -m elf_i386 -shared -o shared foo.o --version-script foo.t > objdump -dw libfoo.so > > libfoo.so: file format elf32-i386 > > > Disassembly of section .text: > > 00000140 <foo>: > 140: c3 ret > > 00000141 <_start>: > 141: 8d 81 98 ef ff ff lea -0x1068(%ecx),%eax > objdump -dw pie > > pie: file format elf32-i386 > > > Disassembly of section .text: > > 00000168 <foo>: > 168: c3 ret > > 00000169 <_start>: > 169: 8d 81 98 ef ff ff lea -0x1068(%ecx),%eax > objdump -dw static > > static: file format elf32-i386 > > > Disassembly of section .text: > > 08048074 <foo>: > 8048074: c3 ret > > 08048075 <_start>: > 8048075: 8d 81 f8 ef ff ff lea -0x1008(%ecx),%eax > objdump -dw shared > > shared: file format elf32-i386 > > > Disassembly of section .text: > > 000000d0 <foo>: > d0: c3 ret > > 000000d1 <_start>: > d1: 8d 81 a0 ef ff ff lea -0x1060(%ecx),%eax > readelf -SW libfoo.so | grep ".got " || true > readelf -SW pie | grep ".got " || true > readelf -SW static | grep ".got " || true > readelf -SW shared | grep ".got " || true > [hjl@gnu-6 symbolic-6]$ > > The same goes for Linux/x86-64. > > -- > Configure bugmail: http://sourceware.org/bugzilla/userprefs.cgi?tab=email > ------- You are receiving this mail because: ------- > You are on the CC list for the bug. -- Configure bugmail: http://sourceware.org/bugzilla/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are on the CC list for the bug. _______________________________________________ bug-binutils mailing list bug-binutils@gnu.org https://lists.gnu.org/mailman/listinfo/bug-binutils
