https://sourceware.org/bugzilla/show_bug.cgi?id=33386
Bug ID: 33386
Summary: ARM/Thumb PIE link corrupts first instruction in
`.text`
Product: binutils
Version: 2.43.1
Status: UNCONFIRMED
Severity: normal
Priority: P2
Component: ld
Assignee: unassigned at sourceware dot org
Reporter: petr at cerninovi dot cz
Target Milestone: ---
Created attachment 16315
--> https://sourceware.org/bugzilla/attachment.cgi?id=16315&action=edit
source code, linker script, build script
When linking a minimal Thumb function as PIE for Cortex-M33, the first
instruction of the first function in `.text` is corrupted in the linked ELF:
the low byte becomes `0x00`.
Object code is correct; corruption appears at link stage with `-pie`. Removing
`-pie` avoids the corruption.
Toolchain: Arm GNU Toolchain 14.2.Rel1 (Build arm-14.52) 2.43.1.20241119
Target: `arm-none-eabi` (Cortex-M33, Thumb)
Host OS: Linux
-------------------------------------------------------------------
Source code (main.c):
int answer_for_everything(void) {
return 42;
}
-------------------------------------------------------------------
Build commands:
arm-none-eabi-gcc -mcpu=cortex-m33 -mthumb -Os -fpie main.c -o main.o
arm-none-eabi-ld -T linker.ld -pie main.o -o main.elf
-------------------------------------------------------------------
Object file (correct):
00000000 <answer_for_everything>:
0: 202a movs r0, #42
2: 4770 bx lr
-------------------------------------------------------------------
Linked ELF with `-pie` (corrupted):
00000000 <answer_for_everything>:
0: 2000 movs r0, #0 <-- low byte became 0x00
2: 4770 bx lr
The problem consistently affects the first instruction at `.text + 0` (the very
first byte in the first PT_LOAD RX segment).
I've attached a complete example showing how to reproduce the bug.
--
You are receiving this mail because:
You are on the CC list for the bug.
