@DanielGibson Well, this is annoying. I'm explicitly using -std=c99 but for some reason Travis is still not seeing sinf, cosf, etc., which are supposed be standard in c99. Do you know the "right" way to fix this?

(see https://travis-ci.org/StrangeZak/Handmade-Math/jobs/217910297)

looks like it can't find the functions at link time, try adding -lm :)

Also, not sure what -isystem is supposed to do here, but in the GCC manpage it sounds like it needs an additional argument (directory to headers?), but either way it doesn't sound like it should be needed there

-isystem was an attempt to mimic the includes that were being used with our old test framework. Suffice to say, it didn't work and I can get rid of it.

@DanielGibson Well, clang is happy now but gcc is not. I'm not sure why, since the -lm flag should be available for gcc as far as I can tell. Any ideas?

https://travis-ci.org/StrangeZak/Handmade-Math/jobs/218082438

Yep. The problem is basically described at http://stackoverflow.com/questions/45135/why-does-the-order-in-which-libraries-are-linked-sometimes-cause-errors-in-gcc and http://www.network-theory.co.uk/docs/gccintro/gccintro_18.html
If the problem happens depends on whether the compiler defaults to passing --as-needed to the linker or not.

TL;DR: put the -lfoo after the source/object file that needs it, in your case make -lm the very last argument of the command

There it is! Thanks for the advice on that. I'm still rather new to compiling C projects, as you can see...

@StrangeZak What do you think? Shall I squash and merge?

no problem, I'm glad I could help :)

Is this good to merged just noticed this sorry. @bvisness