On 28 January 2016 at 22:20, Jim Wilson jim.wilson@linaro.org wrote:
This is a minor arm port bug. Use both -mlong-calls and -pg and you get bl __gnu_mcount_nc instead of the long call to mcount that I expected. The MIPS port does get this right, and uses a longcall for mcount if longcalls are enabled.
Hi Jim,
We have this bug in LLVM:
https://llvm.org/bugs/show_bug.cgi?id=23969
Which deals with the problems of mcount messing up the prologue, and it seems to affect both kernel and chromium.
I was delaying the decision to move to __gnu_mcount_nc on ARM unconditionally, but if GCC requires the -mlong-calls option, then I think we could make it work very easily.
Is this in line of what you were suggesting, or am I crossing the wires here?
cheers, --renato