warning: gcc linker scripts in demo examples

jblackarty wrote on Friday, October 26, 2012:

I think most linker scripts that come with demo examples for GCC should be improved. They are not suitable for release build in case when developer releases firmware in .hex format retreived with:

objcopy -O ihex -j .text -j .data <program>.elf  "<program>.hex"

(Restricting output with .text and .data sections required by SEGGER J-Flash utility used for flashing in production, because it fails program .hex file which contains regions outside of flash memory for given MCU).
This restriction results in some sections relocated to flash to be missed. For example, for CORTEX_MPU_LPC1768_GCC_RedSuite demo based application:
1. privileged_functions will be skipped, which causes given firmware to not work at all (it will work until scheduler starts)
2. .ARM.extab and .ARM.exidx will be skipped, which MAY cause problems if program uses newlib exception handling/unwind

I just wanted to warn people who base their applications completely on demo examples provided with FreeRTOS.

jblackarty wrote on Friday, October 26, 2012:

I found that .ARM.extab and .ARM.exidx must not be placed in .text. So #2 item isn’t actual.Only privileged_functions is problematic.
Also there are .preinit_*/._init_*/.fini_* array input sections missed which optionally must be linked if you use init constructors (which may be used in C, not C++ only !)

edwards3 wrote on Friday, October 26, 2012:

I think the Red Suite linker scripts are created by the Red Suite tool.