Here build_data_member_initialization got confused by the
initialization of a field of local variable f and thought it was
initializing a field of S; when we then went looking for that field in
S, we didn't find it, and crashed. But if the target of an
initialization is a member of a VAR_DECL, it can't be part of *this,
so we should ignore it here.
Tested x86_64-pc-linux-gnu, applying to trunk.
commit 227008348567729cd124bea44227771681361c40
Author: Jason Merrill <ja...@redhat.com>
Date: Mon Feb 13 15:09:37 2017 -0500
PR c++/79461 - ICE with lambda in constexpr constructor
* constexpr.c (build_data_member_initialization): Ignore
initialization of a local variable.
diff --git a/gcc/cp/constexpr.c b/gcc/cp/constexpr.c
index bfdde9e..004bb45 100644
--- a/gcc/cp/constexpr.c
+++ b/gcc/cp/constexpr.c
@@ -379,6 +379,9 @@ build_data_member_initialization (tree t,
vec<constructor_elt, va_gc> **vec)
if (TREE_CODE (member) == COMPONENT_REF)
{
tree aggr = TREE_OPERAND (member, 0);
+ if (TREE_CODE (aggr) == VAR_DECL)
+ /* Initializing a local variable, don't add anything. */
+ return true;
if (TREE_CODE (aggr) != COMPONENT_REF)
/* Normal member initialization. */
member = TREE_OPERAND (member, 1);
diff --git a/gcc/testsuite/g++.dg/cpp1z/constexpr-lambda15.C
b/gcc/testsuite/g++.dg/cpp1z/constexpr-lambda15.C
new file mode 100644
index 0000000..7e05481
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1z/constexpr-lambda15.C
@@ -0,0 +1,10 @@
+// PR c++/79461
+// { dg-options -std=c++1z }
+
+struct S {
+ constexpr S(int i) {
+ auto f = [i]{};
+ }
+};
+int main() {}
+
