I'm trying to figure out how to do a traditional instrumented profile with LDC.  All docs that I've managed to find so far say to use -fprofile-instr-generate, but when I try that, I get a ton of linker errors complaining of undefined reference to the symbol:

	__llvm_profile_instrument_target

What gives?  I'm guessing I need to specify some additional LLVM libraries for this?

I'm using the official Debian ldc package, btw.  Is there possibly a missing dependency on some llvm libraries?


T

-- 
If the comments and the code disagree, it's likely that *both* are wrong. -- Christopher

On Wednesday, 25 April 2018 at 17:31:06 UTC, H. S. Teoh wrote:
> I'm trying to figure out how to do a traditional instrumented profile with LDC.  All docs that I've managed to find so far say to use -fprofile-instr-generate, but when I try that, I get a ton of linker errors complaining of undefined reference to the symbol:
>
> 	__llvm_profile_instrument_target
>
> What gives?  I'm guessing I need to specify some additional LLVM libraries for this?

How are you linking? Do you let LDC link and is `-fprofile-instr-generate` passed during linking aswell?

The profiling runtime must be linked in. On Unixes, the file is "libldc_rt.profile-x86_64.a".

- Johan

On Wednesday, 25 April 2018 at 17:31:06 UTC, H. S. Teoh wrote:
> I'm trying to figure out how to do a traditional instrumented profile with LDC.  All docs that I've managed to find so far say to use -fprofile-instr-generate, but when I try that, I get a ton of linker errors complaining of undefined reference to the symbol:
>
> 	__llvm_profile_instrument_target
>
> What gives?  I'm guessing I need to specify some additional LLVM libraries for this?

I’d suggest perf if you are on Linux. It also tracks kernel-land calls if you have permissions.

Just compile with debug symbols and run:

perf record -g ./app ...
perf report

Works for both DMD and LDC. It is sampling, so might not be accurate for short lived stuff.

>
> I'm using the official Debian ldc package, btw.  Is there possibly a missing dependency on some llvm libraries?
>
>
> T