[Bug c++/61575] New: [4.9 Regression] Bogus invalid initialization of reference of type 'const D&' from expression of type '<brace-enclosed initializer list>'

[ppluzhnikov at google dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61575

            Bug ID: 61575
           Summary: [4.9 Regression] Bogus invalid initialization of
                    reference of type 'const D&' from expression of type
                    '<brace-enclosed initializer list>'
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: ppluzhnikov at google dot com

Google ref: b/15094102

The following test compiles with gcc-4.8 and trunk, fails with current
gcc-4_9-branch:

/// -- cut ---
struct D
{
  const int &x;
  const int &y;
};
int Create (const D &);

void fn1 ()
{
  Create ( { {}, {} });
}
/// -- cut ---

gcc-svn-4_9-r211828/bin/gcc  -c -std=c++11 t.ii

gcc-svn-4_9-r211175/bin/gcc  -c -std=c++11  t.ii
t.ii: In function 'void fn1()':
t.ii:10:22: error: invalid initialization of reference of type 'const D&' from
expression of type '<brace-enclosed initializer list>'
   Create ( { {}, {} });
                      ^
t.ii:6:5: note: in passing argument 1 of 'int Create(const D&)'
 int Create (const D &);
     ^


The source is accepted by Clang, and trunk (@r211826). It was rejected by
trunk in the past:

OK gcc-svn-r195189/bin/gcc
OK gcc-svn-r197259/bin/gcc
OK gcc-svn-r198246/bin/gcc
OK gcc-svn-r198956/bin/gcc
OK gcc-svn-r199779/bin/gcc
OK gcc-svn-r199793/bin/gcc
OK gcc-svn-r199956/bin/gcc
OK gcc-svn-r200178/bin/gcc
                            ... broke somewhere here
KO gcc-svn-r210292/bin/gcc
KO gcc-svn-r210629/bin/gcc
                            ... refixed somewhere here
OK gcc-svn-r211159/bin/gcc
OK gcc-svn-r211286/bin/gcc
OK gcc-svn-r211479/bin/gcc
OK gcc-svn-r211743/bin/gcc
OK gcc-svn-r211826/bin/gcc