shims/super/cc: do not pass -pipe

[fxcoudert]

I've been wondering for a long time why we pass -pipe to C compilers systematically.

• On modern filesystems its effect is homeopathic
• it has no effect with modern clang, because the assembler is now integrated into clang, so only the linker is called as a separate, and it never supported pipes anyway
• the only other compiler we use for a few formulas is GCC, but even there the effect is marginal on modern OSes

At least, it did not hurt. Well, until clang 16 broke pipe input to the assembler: there, passing -pipe can make GCC actually fail to compile. See OpenMathLib/OpenBLAS#4888 for details.

I'll be filing a bug with Apple about that (it's a regression in clang), but I don't expect it to be fixed soon. Given that -pipe use is historical, I think it's time to say goodbye to it.

[Bo98]

Was originally added in 5c62420. So yes, very historical

• On modern filesystems its effect is homeopathic

Disk I/O on CI is funky, especially Intel where it's got qemu layers and is slower than native peformance. So it made sense to have as a default.

But if it's never used anyway on Clang then removing it makes sense.

[MikeMcQuaid]

Thanks @fxcoudert!