TNTC=No broken on macOS

Summary

If we disable TNTC on macOS, the compiler breaks.

Steps to reproduce

Disable TNTC and try to build GHC

Expected behavior

A successful build of GHC.

Environment

• GHC version used: GHC HEAD ~ Jan 2019

Optional:

• Operating System: macOS
• System Architecture: x86_64

Bisection got me to narrow it down to likely be within:

git log --reverse 8b007abbeb3045900a11529d907a835080129176~1...5a8b8434bd79e5597a66a2779012082e369b340b

and I suspect this commit might be at fault: 8b007abb

We end up with something like

.text
.align 3
Lc4l:
Lc4l:
        jmp Lc4u
.const_data
.align 3
.align 0
_Lc4l_info:
        .quad   Lc4l
        .quad   259
        .long   30
        .long   0

in the assembly. Not the redefinition of Lc4l? This is where the assembler chokes on.