re PR c++/79639 (ICE with -O and constexpr)

	PR c++/79639
	* constexpr.c (cxx_eval_store_expression): If *valp is a PTRMEM_CST,
	call cplus_expand_constant on it first.

	* g++.dg/cpp1y/constexpr-79639.C: New test.

From-SVN: r245635

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 385c509..26ead8a 100644 (file)
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,9 @@
+2017-02-21  Jakub Jelinek  <jakub@redhat.com>
+
+       PR c++/79639
+       * constexpr.c (cxx_eval_store_expression): If *valp is a PTRMEM_CST,
+       call cplus_expand_constant on it first.
+
 2017-02-19  Jason Merrill  <jason@redhat.com>
 
        PR c++/78139 - destructor needed by new-expression

diff --git a/gcc/cp/constexpr.c b/gcc/cp/constexpr.c
index fc7d46c..14af617 100644 (file)
--- a/gcc/cp/constexpr.c
+++ b/gcc/cp/constexpr.c
@@ -3517,11 +3517,12 @@ cxx_eval_store_expression (const constexpr_ctx *ctx, tree t,
         wants to modify it.  */
       if (*valp == NULL_TREE)
        {
-         *valp = new_ctx.ctor = build_constructor (type, NULL);
-         CONSTRUCTOR_NO_IMPLICIT_ZERO (new_ctx.ctor) = no_zero_init;
+         *valp = build_constructor (type, NULL);
+         CONSTRUCTOR_NO_IMPLICIT_ZERO (*valp) = no_zero_init;
        }
-      else
-       new_ctx.ctor = *valp;
+      else if (TREE_CODE (*valp) == PTRMEM_CST)
+       *valp = cplus_expand_constant (*valp);
+      new_ctx.ctor = *valp;
       new_ctx.object = target;
     }
 

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 02e4dec..342f23f 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,8 @@
 2017-02-21  Jakub Jelinek  <jakub@redhat.com>
 
+       PR c++/79639
+       * g++.dg/cpp1y/constexpr-79639.C: New test. 
+
        PR target/79633
        * gcc.target/i386/mpx/pr79633.c: New test.
 

diff --git a/gcc/testsuite/g++.dg/cpp1y/constexpr-79639.C b/gcc/testsuite/g++.dg/cpp1y/constexpr-79639.C
new file mode 100644 (file)
index 0000000..03e6b84
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1y/constexpr-79639.C
@@ -0,0 +1,27 @@
+// PR c++/79639
+// { dg-do compile { target c++14 } }
+
+struct A
+{
+  void foo () {}
+  void bar () {}
+};
+typedef void (A::*T) ();
+
+constexpr T
+foo (T f)
+{
+  f = 0;
+  return f;
+}
+
+constexpr T
+bar (T f)
+{
+  f = &A::bar;
+  return f;
+}
+
+constexpr T a = foo (&A::foo);
+constexpr T b = foo (&A::foo);
+static_assert (a == nullptr, "");