Hi!
The following testcase ICEs, because we assert that we see a COMPOUND_EXPR
only for static data member in a volatile struct, but as the testcase shows,
we can see it also if using some component of the static data member.
Fixed by using get_base_address, plus, as the check isn't as cheap as
before, turn the assert into a checking assert only.
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
2018-03-27 Jakub Jelinek <ja...@redhat.com>
PR c++/85061
* c-common.c (fold_offsetof_1) <case COMPOUND_EXPR>: Assert that
get_base_address of the second operand is a VAR_P, rather than the
operand itself, and use gcc_checking_assert instead of gcc_assert.
* g++.dg/ext/builtin-offsetof3.C: New test.
--- gcc/c-family/c-common.c.jj 2018-03-13 00:38:23.809662252 +0100
+++ gcc/c-family/c-common.c 2018-03-24 15:21:36.171485128 +0100
@@ -6272,7 +6272,7 @@ fold_offsetof_1 (tree expr, enum tree_co
case COMPOUND_EXPR:
/* Handle static members of volatile structs. */
t = TREE_OPERAND (expr, 1);
- gcc_assert (VAR_P (t));
+ gcc_checking_assert (VAR_P (get_base_address (t)));
return fold_offsetof_1 (t);
default:
--- gcc/testsuite/g++.dg/ext/builtin-offsetof3.C.jj 2018-03-26
11:54:54.338627270 +0200
+++ gcc/testsuite/g++.dg/ext/builtin-offsetof3.C 2018-03-26
11:54:07.992610454 +0200
@@ -0,0 +1,14 @@
+// PR c++/85061
+// { dg-do compile }
+
+struct B { int a, b; };
+struct A
+{
+ static int x[2];
+ static int y;
+ static B z;
+};
+
+int i = __builtin_offsetof (volatile A, x[0]); // { dg-error "cannot apply
'offsetof' to static data member 'A::x'" }
+int j = __builtin_offsetof (volatile A, y); // { dg-error "cannot apply
'offsetof' to static data member 'A::y'" }
+int k = __builtin_offsetof (volatile A, z.a); // { dg-error "cannot apply
'offsetof' to a non constant address" }
Jakub
