If the jail environment is 10, Mk/Scripts/ports_env.sh returns the following line: CC_OUTPUT_921dbbb2_65ad290d=error: invalid value 'c++14' in '-std=c++14' CC_OUTPUT_921dbbb2_f2776b26=error: invalid value 'c++17' in '-std=c++17' CC_OUTPUT_921dbbb2_160933ec=error: invalid value 'gnu++14' in '-std=gnu++14' CC_OUTPUT_921dbbb2_fb62803b=error: invalid value 'gnu++17' in '-std=gnu++17' About that, processonelog.sh returns the reason as bad_C++_code. It does not have enough information.
(In reply to Tatsuki Makino from comment #0) It's "normal" I have that in poudriere in mine as well (13-current) and it was like that in older versions and builds don't fail because of it
I do not know when it will be, but 13.x-RELEASE returns CC_OUTPUT_xxxxxxxx_xxxxxxxx=error: invalid value 'c++2?' in '-std=c++2?'. If the reason for the build failure is a patch (or reasons to appear after reason="bad_C++_code"), poudriere reports the reason bad_C++_code.