https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121244
Bug ID: 121244
Summary: Wsfinae-incomplete very unhelpfull and probably false
positives
Product: gcc
Version: 16.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: linux at carewolf dot com
Target Milestone: ---
Doing a trial build of Qt with git gcc from 24/7 2025. I hit multiple errors
under -Werror with the new default on Wsfinae-incomplete.
The default warning is
/src/qt5/qtbase/src/corelib/text/qanystringview.h:39:7: error: defining
‘QAnyStringView’, which previously failed to be complete in a SFINAE context
[-Werror=sfinae-incomplete=]
39 | class QAnyStringView
Then it tells me to use -Wsfinae-incomplete=2 to see any details about the
warning like where the substitution failed, but no entries shown are about
QAnyStringView, but instead failures to complete places where it is
intentional.
I seems to me when it warns about a previous failure to complete SFINAE, it
should tell where that was by default and not instruct us to compile again with
the warning set to report more false positives.
