https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81915
Arthur Norman <acn1 at cam dot ac.uk> changed:
What |Removed |Added
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CC| |acn1 at cam dot ac.uk
--- Comment #3 from Arthur Norman <acn1 at cam dot ac.uk> ---
Created attachment 47280
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=47280&action=edit
test script to illustrate the linker problems with static inline thread_local
and the Microsoft object format
This is an issue with linking under Cygwin and so may be related to the object
format used on Windows. My example behaves OK on bot x86_64 and ARM Linux (asn
on a Mac) but fails under Cygwin and the mingw32 compilers used via cygwin. It
looks like a failure to transcribe the "inline" (ir multiple definitions OK)
attribute to the ¥thread-local initialization routine. The original bug report
has a std::string and one might worry lest std::string was special or
complicated. My one here just uses simple piain data.
It is possible to achieve something that works on Windows because if I put the
definitions of the static thread_local things inside an inline function rather
than just within a class having several copies in separate compilation units
does not cause link-time problems, so I find it hard to believe that this is an
unsurmountable problem on Windows.
