Old SDK12.1 based bootloader not working when compiled with arm gcc 9.2.1

[georgn]

I have a project that I've joined recently that is based on SDK12.1. The bootloader does not seem to work when compiled with a currently arm-gcc version (9.2.1). It does work when compiled with 4.9.3. By "not work" I mean the bootloader gets stuck, will not DFU nor will it start the application.

Some background:

The project has a bootloader and an application component. The bootloader handles DFU chores (the application goes into DFU mode by NVIC_SystemReset() and the bootloader does the heavy lifting). I was attempting to build and flash from a mac rather than the crusty Linux VM I was given.  I seem to be able to do "all the things" (flash, use the gdb/segger rtt to see console messages). I can build everything on the Mac but replace the bootloader hex file with one from the crusty Linux VM just before flashing, everything works.

So before I burn a bunch of time in debugging, has anybody else seen "weird" behaviour migrating from 4.9.x gcc to something more recent?

Thanks.

[Vidar Berg]

Hello,

Please try disabling the link-time optimization (i.e., remove '-flto' option from Makefile) and see if it gives the same result. We have had some problems with this optimization and certain releases of GCC. As stated in the release notes, SDK v12. was tested and verified with the 4.9 2015q3 release.