On 8/31/21 9:02 AM, Jonathan Wakely wrote:
> It looks like my questions about this patch never got an answer, and
> it never got applied.
> 
> Could somebody say whether TLS is enabled for native *-*-mingw*
> builds? If it is, then we definitely need to add GCC_CHECK_TLS to the
> cross-compiler config too.
> 
> For a linux-hosted x86_64-w64-mingw32 cross compiler I see TLS is not enabled:
> 
> /* Define to 1 if the target supports thread-local storage. */
> /* #undef _GLIBCXX_HAVE_TLS */
> 
> 
> 
> 
> On Mon, 19 Feb 2018 at 08:59, Hugo Beauzée-Luyssen <hugo@beauzee.fr> wrote:
>>
>> libstdc++-v3: Check for TLS support on mingw
>>
>> 2018-02-16  Hugo Beauzée-Luyssen  <hugo@beauzee.fr>
>>
>>      * crossconfig.m4: Check for TLS support on mignw
>>      * configure: regenerate
>>
>> Index: libstdc++-v3/crossconfig.m4
>> ===================================================================
>> --- libstdc++-v3/crossconfig.m4 (revision 257730)
>> +++ libstdc++-v3/crossconfig.m4 (working copy)
>> @@ -197,6 +197,7 @@ case "${host}" in
>>       GLIBCXX_CHECK_LINKER_FEATURES
>>       GLIBCXX_CHECK_MATH_SUPPORT
>>       GLIBCXX_CHECK_STDLIB_SUPPORT
>> +    GCC_CHECK_TLS
>>       ;;
>>     *-netbsd*)
>>       SECTION_FLAGS='-ffunction-sections -fdata-sections'

According to MSYS2 native from 
https://mirror.msys2.org/mingw/ucrt64/mingw-w64-ucrt-x86_64-gcc-10.3.0-5-any.pkg.tar.zst:

x86_64-w64-mingw32/bits/c++config.h:#define _GLIBCXX_HAVE_TLS 1

So yes.