On 29/04/2021 21:43, Ian Molton wrote: > Hi, > > I'm attempting to build my project, which does not use libc, or libm, > but I do want to link with libgcc. > > additionally, I don't want any startup code to be linked - the project > is intended to be fully standalone. >
If you don't use any functions from these libraries, nothing from them will be linked into your project - it doesn't matter if the linker has them. (I can't remember the details for the avr, but often "libm" is actually empty, and exists only for compatibility - all the maths functions are frequently included in the main libc.) Sometimes (again, this is from other targets rather than the avr, which I have not used for many years) it is useful to provide stubs of functions like "exit()" and "atexit()" - just add these as extra empty functions in your code. That will ensure the library versions are not used, and they do not pull in any other bits and pieces.