# dependencies picking up strange CFLAGS

**URL:** https://discourse.julialang.org/t/dependencies-picking-up-strange-cflags/11185
**Category:** Internals & Design
**Created:** [May 27, 2018, 6:02pm UTC](https://discourse.julialang.org/t/dependencies-picking-up-strange-cflags/11185 "2018-05-27T18:02:44Z")
**Posts on this page:** 1
**Page:** 1

<div class="post-metadata">

### Author: ![schnaitterm](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/schnaitterm/32/6807_2.png) [@schnaitterm](https://discourse.julialang.org/u/schnaitterm)
#### Post date: [May 27, 2018, 6:02pm UTC](https://discourse.julialang.org/t/dependencies-picking-up-strange-cflags/11185/1 "2018-05-27T18:02:44Z")

</div>

I’m not sure if this happens on other platforms as well, but I am noticing that dependencies like GMP are picking up strange flags like “-march=k8 -mtune=k8” on macOS, even when MARCH is set to ‘native’ (it actually puts -march=native and then cancels it out by adding the other, wrong ones). Does anyone know where all of these flags are coming from?