Always build with -ggdb3

[xobs]

Right now, debug symbols are only turned on when compiling with DEBUG=1. I ran a test where I built the image twice: Once with -ggdb3 and once with (i.e. adding a space to ensure both were built from dirty git repos).

The resulting file was 8 bytes larger over 228384 bytes, and much of the resulting binary was identical. I suspect there may be other conflating factors including the order in which symbols are generated.

Is there a reason circuitpython isn't normally built with -ggdb3?

[tannewt]

No, I think @jepler has wanted this too.

[jepler]

I do. Also, the step of always running 'strip' after linking circuitpython needs to be removed.

[dhalbert]

I'm confused by this. a gdb build normally has many symbol strings in it, which makes it a lot larger. Are we talking about the .elf only? We of course don't want these strings in the .bin/.uf2.

[xobs]

A gdb build normally has many symbol strings, however it's missing various .debug_* sections. These sections can be used to go from $pc locations back to function locations. Without these sections you can kind of get a sense of where you are in the program, but if you're in a function that got inlined then the debugger has no idea where you are. Additional information about symbol sizes may also be lost, and you won't get symbols such as preprocessor #define values.

These sections don't get copied to the .bin or .uf2 file, they are only present in the .elf file.

Note that -ggdb3 got accidentally included on the NRF port as part of 1d0781b.

[dhalbert]

-ggdb3 is now set explicitly in nrf, stm, litex, esp32s2, and atmel-samd` Makefiles.