fbf41b5267
See `docs/ELF/linker_script.rst` for the new computation for sh_addr and sh_addralign.
`ALIGN(section_align)` now means: "increase alignment to section_align"
(like yet another input section requirement).
The "start of section .foo changes from 0x11 to 0x20" warning no longer
makes sense. Change it to warn if sh_addr%sh_addralign!=0.
To decrease the alignment from the default max_input_align,
use `.output ALIGN(8) : {}` instead of `.output : ALIGN(8) {}`
See linkerscript/section-address-align.test as an example.
When both an output section address and ALIGN are set (can be seen as an
"undefined behavior" https://sourceware.org/ml/binutils/2020-03/msg00115.html),
lld may align more than GNU ld, but it makes a linker script working
with GNU ld hard to break with lld.
This patch can be considered as restoring part of the behavior before D74736.
Differential Revision: https://reviews.llvm.org/D75724
35 lines
1.5 KiB
Plaintext
35 lines
1.5 KiB
Plaintext
# REQUIRES: x86
|
|
## Test ALIGN when specifying the output section address.
|
|
|
|
# RUN: echo '.globl _start; _start: ret; \
|
|
# RUN: .data.rel.ro; .balign 8; .byte 0; \
|
|
# RUN: .data; .byte 0; \
|
|
# RUN: .bss; .balign 32; .byte 0' | \
|
|
# RUN: llvm-mc -filetype=obj -triple=x86_64 - -o %t.o
|
|
# RUN: ld.lld -T %s %t.o -o %t 2>&1 | FileCheck --check-prefix=WARN %s --implicit-check-not=warning:
|
|
# RUN: llvm-readelf -S %t | FileCheck %s
|
|
|
|
# WARN: warning: address (0x10004) of section .data.rel.ro is not a multiple of alignment (8)
|
|
# WARN: warning: address (0x20008) of section .bss is not a multiple of alignment (32)
|
|
|
|
# CHECK: Name Type Address Off Size ES Flg Lk Inf Al
|
|
# CHECK-NEXT: NULL 0000000000000000 000000 000000 00 0 0 0
|
|
# CHECK-NEXT: .text PROGBITS 0000000000010000 001000 000001 00 AX 0 0 4
|
|
# CHECK-NEXT: .data.rel.ro PROGBITS 0000000000010004 001004 000005 00 WA 0 0 8
|
|
# CHECK-NEXT: .data PROGBITS 0000000000020000 002000 000001 00 WA 0 0 1
|
|
# CHECK-NEXT: .bss NOBITS 0000000000020008 002001 000019 00 WA 0 0 32
|
|
|
|
SECTIONS {
|
|
.text 0x10000 : { *(.text) }
|
|
## The output .data.rel.ro starts at 0x10004.
|
|
## The input .data.rel.ro starts at 0x10008 and ends at 0x10009.
|
|
## sh_size(.data.rel.ro) = 0x10009-0x10004 = 0x5.
|
|
.data.rel.ro ALIGN(4) : { *(.data.rel.ro) }
|
|
|
|
.data 0x20000 : { *(.data) }
|
|
## The output .bss starts at 0x20008.
|
|
## The input .bss starts at 0x20020 and ends at 0x20021.
|
|
## sh_size(.bss) = 0x20021-0x20008 = 0x19.
|
|
.bss ALIGN(8) : { *(.bss) }
|
|
}
|