Re: [PATCH][gdb/build] Fix build with undefined CXX_STD_THREAD

[Tom de Vries <tdevries@suse.de>]

On 9/7/21 5:19 PM, Tom de Vries wrote:
> I find:
> ...
> CXX_DIALECT='-std=gnu++11'
> ...
> in the config.log, but that setting is not used when checking for
> CXX_STD_THREAD, so we have:
> ...
> configure:14614: checking for std::thread
> configure:14631: g++ -c -pthread -Wall -O2 -g     conftest.cpp >&5
> In file included from /usr/include/c++/4.8/thread:35:0,
>                  from conftest.cpp:167:
> /usr/include/c++/4.8/bits/c++0x_warning.h:32:2: error: #error This file
> requires compiler and library support for the ISO C++ 2011 standard.
> This support is currently experimental, and must be enabled with the
> -std=c++11 or -std=gnu++11 compiler options.
>  #error This file requires compiler and library support for the \
>   ^
> conftest.cpp: In function 'int main()':
> conftest.cpp:172:1: error: 'thread' is not a member of 'std'
>  std::thread t(callback);
>  ^
> conftest.cpp:172:13: error: expected ';' before 't'
>  std::thread t(callback);
>              ^
> configure:14631: $? = 1
> ...
> 
> It could be that:
> ...
> $ g++ -std=gnu++11 -c -pthread -Wall -O2 -g     conftest.cpp
> ...
> actually would succeed.

Filed PR28318 - "[gdb/build] std::thread support configure check does
not use CXX_DIALECT"  here (
https://sourceware.org/bugzilla/show_bug.cgi?id=28318 ).

Thanks,
- Tom