[Bug other/87199] Thread local storage dynamic initialization behaviour differs Linux vs macOS

[drikosev at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87199

Ev Drikos <drikosev at gmail dot com> changed:

           What    |Removed                     |Added
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                 CC|                            |drikosev at gmail dot com

--- Comment #2 from Ev Drikos <drikosev at gmail dot com> ---
(In reply to Eric Gallager from comment #1)
> My first guess would be that the difference is Linux has native TLS, whereas
> macOS only has emutls, which would be bug 52268. I'll wait for someone else
> to confirm, though.


Not really sure if my response is indeed the confirmation you want. 

If I compile the above example in macOS High Sierra (10.13) with the much older
GNU gcc-4.8.5, then the output is "constest". Whereas with the newer gcc-8.2 I
see the same results with the OP.

$ g++ --version && uname -r
g++ (GCC) 4.8.5
Copyright (C) 2015 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

17.5.0
$ g++  -g  -std=c++11 -c -I . main.c
$ g++  -g  -std=c++11 -c -I . lib.cpp
$ g++  -o main main.o lib.o
$ ./main
constest$ 
$ g++8  -g  -std=c++11 -c -I . main.c
$ g++8  -g  -std=c++11 -c -I . lib.cpp
$ g++8  -o main main.o lib.o
$ ./main
$

Ev. Drikos