[Bug c++/66543] False positive warning "variable set but not used"

[jason at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66543

--- Comment #4 from Jason Merrill <jason at gcc dot gnu.org> ---
Author: jason
Date: Wed Apr 20 13:24:17 2016
New Revision: 235279

URL: https://gcc.gnu.org/viewcvs?rev=235279&root=gcc&view=rev
Log:
        PR c++/66543 - -Wunused-but-set* false positives

        * expr.c (mark_exp_read): Handle NON_DEPENDENT_EXPR.
        * pt.c (make_pack_expansion): Call mark_exp_read.
        * semantics.c (finish_id_expression): Call mark_type_use in
        unevaluated context.

Added:
    branches/gcc-6-branch/gcc/testsuite/g++.dg/warn/Wunused-parm-7.C
    branches/gcc-6-branch/gcc/testsuite/g++.dg/warn/Wunused-parm-8.C
    branches/gcc-6-branch/gcc/testsuite/g++.dg/warn/Wunused-var-24.C
    branches/gcc-6-branch/gcc/testsuite/g++.dg/warn/Wunused-var-25.C
Modified:
    branches/gcc-6-branch/gcc/cp/ChangeLog
    branches/gcc-6-branch/gcc/cp/expr.c
    branches/gcc-6-branch/gcc/cp/pt.c
    branches/gcc-6-branch/gcc/cp/semantics.c