[Bug analyzer/93543] New: [10 regression] bootstrap with clang 9.0.1 fails in analyzer: reinterpret_cast from 'nullptr_t' to 'function *' is not allowed

[gerald at pfeifer dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93543

            Bug ID: 93543
           Summary: [10 regression] bootstrap with clang 9.0.1 fails in
                    analyzer: reinterpret_cast from 'nullptr_t' to
                    'function *' is not allowed
           Product: gcc
           Version: 10.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: analyzer
          Assignee: dmalcolm at gcc dot gnu.org
          Reporter: gerald at pfeifer dot com
  Target Milestone: ---

This was originally filed in the FreeBSD bug tracker against lang/gcc10-devel,
cf. https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=243681

A user reported

 
/usr/ports/lang/gcc10-devel/work/gcc-10-20200126/gcc/analyzer/engine.cc:2971:13:
error: 
      reinterpret_cast from 'nullptr_t' to 'function *' is not allowed
  v.m_fun = reinterpret_cast<function *> (NULL);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

 
/usr/ports/lang/gcc10-devel/work/gcc-10-20200126/gcc/analyzer/engine.cc:2983:21:
error: 
      reinterpret_cast from 'nullptr_t' to 'function *' is not allowed
  return v.m_fun == reinterpret_cast<function *> (NULL);
                    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

in analyzer/engine.cc.

David Malcolm kindly provided a patch that I applied on the FreeBSD side.

This report is to track and ensure this gets fixed in upstream GCC with 
the GCC 10.1 release.