https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89727
Bug ID: 89727
Summary: static thread_local ODR use broken
Product: gcc
Version: 8.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: leppkes at stce dot rwth-aachen.de
Target Milestone: ---
Created attachment 45972
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=45972&action=edit
minimal example of incorrect behavior (static member B::a should be initialized
before first usage).
In the bug example, there are 3 uses of a static thread_local member.
>From my understanding to the C++ Standard, the compiler should initialize the
member before first use (ODR Rule).
Clang and Intel C++ Compiler behave correct from my understanding. GNU C++
initializes too late.
~/gcc_bug$ g++ test.cpp; ./a.out
0
constructing A.
42
42
~/gcc_bug$ icc test.cpp; ./a.out
constructing A.
42
42
42
~/gcc_bug$ clang++ test.cpp; ./a.out
constructing A.
42
42
42
