embedded build_error ai_generated true

ld: section .data overlaps with .bss in region RAM

ID: embedded/linker-section-overlap-ram

Also available as: JSON · Markdown · 中文

92%Fix Rate

84%Confidence

1Evidence

2024-08-05First Seen

Root Cause

The linker script has incorrect memory region definitions or section placement, causing the .data (initialized data) and .bss (zero-initialized data) sections to overlap in RAM, typically due to misaligned start addresses or insufficient region size.

generic

中文

链接脚本中内存区域定义或段放置错误，导致.data段（已初始化数据）与.bss段（零初始化数据）在RAM中重叠，通常由起始地址未对齐或区域大小不足引起。

Official Documentation

https://sourceware.org/binutils/docs/ld/Scripts.html

Workarounds

95% success Edit the linker script (e.g., STM32FLASH.ld) to add explicit alignment between .data and .bss. Example: .data : { *(.data) } >RAM AT>FLASH . = ALIGN(4); .bss : { *(.bss) } >RAM
```
Edit the linker script (e.g., STM32FLASH.ld) to add explicit alignment between .data and .bss. Example: .data : { *(.data) } >RAM AT>FLASH . = ALIGN(4); .bss : { *(.bss) } >RAM
```
88% success Use the --print-memory-usage and --print-map flags to inspect section placement, then adjust the RAM region length to accommodate both sections.
```
Use the --print-memory-usage and --print-map flags to inspect section placement, then adjust the RAM region length to accommodate both sections.
```

中文步骤

Edit the linker script (e.g., STM32FLASH.ld) to add explicit alignment between .data and .bss. Example: .data : { *(.data) } >RAM AT>FLASH . = ALIGN(4); .bss : { *(.bss) } >RAM

Use the --print-memory-usage and --print-map flags to inspect section placement, then adjust the RAM region length to accommodate both sections.

Dead Ends

Common approaches that don't work:

65% fail
Simply increasing the RAM region size in the linker script without adjusting the section start addresses may shift the overlap but not resolve it.
80% fail
Removing the .bss section entirely (by setting all variables to initialized) is not a scalable solution and may cause other linker errors.