I have an open source micromouse robot project. For easier compilation, I use containers (both Podman and Docker should be fine):
make image
make libopencm3
make
This works just fine and generates a main.elf file about 874 kB in size. But that is as long as I fix the arm-none-eabi-gcc-cs to 7.4.0 in the Dockerfile.
If I remove the specific version or set it to 9.2.0, then I get the following error:
$ make
/usr/lib/gcc/arm-none-eabi/9.2.0/../../../../arm-none-eabi/bin/ld: main.elf section `.text' will not fit in region `rom'
/usr/lib/gcc/arm-none-eabi/9.2.0/../../../../arm-none-eabi/bin/ld: region `rom' overflowed by 5288 bytes
collect2: error: ld returned 1 exit status
make: *** [opencm3/libopencm3.rules.mk:204: main.elf] Error 1
What could have changed between those versions?
If I add this line to my Makefile:
LDFLAGS += -specs=nano.specs
Then it compiles just fine with version 9.2.0 and generates a main.elf file about 885 kB in size. But I wonder if the performance would be the same (or equivalent) as before.
Update
I am expecting some performance differences, of course, just like I was expecting some differences in the binary size. But I was wondering if I could expect a higher than 20% difference in performance (specially if it could be now 20% slower).
The new binary is less than 2% bigger, and I would consider this to be "the same" as before. :-D