Identify the Error Message
- Linker script errors usually have descriptive messages. Start by reading the error output carefully.
- Look for symbols that could not be resolved, addresses that overlap, or unexpected memory region behaviors.
Review the Linker Script
- Verify that the linker script matches your microcontroller's or processor's memory specification. Ensure that FLASH and RAM sizes are correctly defined.
- Check the syntax of your script. Common issues arise from missing sections or incorrect memory alignment.
Examine the Memory Sections
- Ensure all sections like `.text`, `.data`, `.bss`, and custom sections have correct memory regions assigned.
- Review attribute placements in your code. For instance, placing code in the correct section by using GCC `__attribute__((section(".mysection")))`.
Check Symbol Definitions
- Review the definitions of symbols that the linker cannot resolve. Ensure they are correctly declared in your code and properly referenced in assembly if used.
- Examine any conditional compilation (`#ifdef`s) that might exclude necessary code in certain build configurations.
Adjust Memory Allocation
- If sections are too large, review code for large arrays or buffers and consider reducing or dynamically allocating them.
- Check alignment settings, especially for sections requiring specific boundaries.
Verify External Dependencies
- Check for library versions and compile settings to ensure compatibility. A mismatched ABI can cause linking errors.
- Make sure paths to external libraries and headers are correctly specified in makefiles or build-system scripts.
Use Map Files
- Enable generation of a map file when linking. This provides a detailed view of memory usage and symbol locations.
- Check the map file to understand where each section and symbol is placed. This helps diagnose overlaps or address alignment issues.
Incremental Approach
- Simplify your code to the smallest example that still causes the error. Segregate sections to see which change resolves the issue.
- Gradually re-integrate your code changes to ensure that errors do not re-appear, enhancing your understanding of the root cause.
Seek Community Help
- If stuck, consult with online communities and forums related to your hardware or toolchain. Often, others have faced similar issues.
- Provide a detailed description and any error messages when seeking assistance to streamline the troubleshooting process.
Example: Custom Section Placement