Comment # 2 on bug 196 from Johannes Pfau

Can you try to get the ASM output? You need to cd to the correct directory,
then run

/Users/johncolvin/Git/GDC/objdir/./gcc/gdc
-B/Users/johncolvin/Git/GDC/objdir/./gcc/
-B/opt/gdc/x86_64-apple-darwin15.0.0/bin/
-B/opt/gdc/x86_64-apple-darwin15.0.0/lib/ -isystem
/opt/gdc/x86_64-apple-darwin15.0.0/include -isystem
/opt/gdc/x86_64-apple-darwin15.0.0/sys-include -Wall -Werror -g -frelease -O2
-nostdinc -pipe -Wno-deprecated -I
../../../../gcc-6-20150719/libphobos/libdruntime -I ./x86_64-apple-darwin15.0.0
-I .  -S ../../../../gcc-6-20150719/libphobos/libdruntime/core/thread.d

(Sounds like something messed up the ASM output. Maybe some incorrect inline
ASM somewhere. IIRC there's also problem with emutls which in some cases
generates invalid names in ASM)