[Bug c++/70106] [4.9/5 Regression][C++11 or above] adding parenthesis [cerr << (var)] cause error: invalid static_cast from type 'const size_t {aka const long unsigned int}' to type 'size_t& {aka long unsigned int&}'

[jason at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70106

--- Comment #8 from Jason Merrill <jason at gcc dot gnu.org> ---
Author: jason
Date: Thu Jul 21 06:29:32 2016
New Revision: 238578

URL: https://gcc.gnu.org/viewcvs?rev=238578&root=gcc&view=rev
Log:
Fix PR c++/70822 (bogus error with parenthesized SCOPE_REF)

gcc/cp/ChangeLog:

        PR c++/70822
        PR c++/70106
        * cp-tree.h (REF_PARENTHESIZED_P): Make this flag apply to
        SCOPE_REFs too.
        * pt.c (tsubst_qualified_id): If REF_PARENTHESIZED_P is set
        on the qualified_id then propagate it to the resulting
        expression.
        (do_auto_deduction): Check REF_PARENTHESIZED_P on SCOPE_REFs
        too.
        * semantics.c (force_paren_expr): If given a SCOPE_REF, just set
        its REF_PARENTHESIZED_P flag.

gcc/testsuite/ChangeLog:

        PR c++/70822
        PR c++/70106
        * g++.dg/cpp1y/auto-fn32.C: New test.
        * g++.dg/cpp1y/paren4.C: New test.

Added:
    branches/gcc-6-branch/gcc/testsuite/g++.dg/cpp1y/auto-fn32.C
    branches/gcc-6-branch/gcc/testsuite/g++.dg/cpp1y/paren4.C
Modified:
    branches/gcc-6-branch/gcc/cp/ChangeLog
    branches/gcc-6-branch/gcc/cp/cp-tree.h
    branches/gcc-6-branch/gcc/cp/pt.c
    branches/gcc-6-branch/gcc/cp/semantics.c
    branches/gcc-6-branch/gcc/testsuite/ChangeLog