scope of configure.optflags, configure.compiler etc. command line variables

[René J.V. Bertin]

On Tuesday September 17 2019 11:49:11 Joshua Root wrote:

I continue to think that compiler choice and options should be something the user can set the default for, without having to replace the standard system compiler drivers (/usr/bin/clang{,++}) with wrapper scripts.

>machine. But -mdynamic-no-pic is incompatible with PIE, which is the
>default since 10.7.

I use -mdynamic-no-pic all the time for almost all my KF5 builds, and *may* only have an issue with a single port that had the option to build with PIE (which I don't see the point of, and I don't think I was using -mdynamic-no-pic at the time). I know that option is incompatible with +universal builds unless you add a linker option I never managed to remember.

I don't even know if -mdynamic-no-pic still gives the same almost free performance gain as it did on PPC (15% or so, I learned about it long ago thanks to the still-lamented Shark tool). But my Mac is now old enough that it makes sense to maximise compilation optimisation. I only don't use LTO systematically because I never managed to get a usable backtrace from slightly more complicated applications with it.

BTW, I do have a LTO PortGroup that adds a +LTO variant and works some magic which seems to work pretty reliably and which I could contribute if there's an interest for it.

R.