In this testcase, the use of COUNT requires us to capture it because
it's bound to a reference, but the lambda doesn't capture, so it's
ill-formed. We're supposed to reject this use in mark_use, but we
were getting confused by the location wrapper. This patch teaches
mark_use to look through location wrappers.
Tested x86_64-pc-linux-gnu, applying to trunk.
commit 91354c9fd7f4773e2c95b36237b88c1f71657097
Author: Jason Merrill <ja...@redhat.com>
Date: Fri Jun 1 23:29:10 2018 -0400
PR c++/85761 - ICE with ill-formed use of const outer variable.
* expr.c (mark_use): Handle location wrappers.
diff --git a/gcc/cp/expr.c b/gcc/cp/expr.c
index 0d0a10ec4a6..9780b75d1cd 100644
--- a/gcc/cp/expr.c
+++ b/gcc/cp/expr.c
@@ -139,6 +139,9 @@ mark_use (tree expr, bool rvalue_p, bool read_p,
break;
}
}
+ temp_override<location_t> l (input_location);
+ if (loc != UNKNOWN_LOCATION)
+ input_location = loc;
expr = process_outer_var_ref (expr, tf_warning_or_error, true);
if (!(TREE_TYPE (oexpr)
&& TYPE_REF_P (TREE_TYPE (oexpr))))
@@ -184,6 +187,11 @@ mark_use (tree expr, bool rvalue_p, bool read_p,
}
break;
default:
+ if (location_wrapper_p (expr))
+ {
+ loc = EXPR_LOCATION (expr);
+ recurse_op[0] = true;
+ }
break;
}
diff --git a/gcc/testsuite/g++.dg/cpp0x/lambda/lambda-const8.C b/gcc/testsuite/g++.dg/cpp0x/lambda/lambda-const8.C
new file mode 100644
index 00000000000..41cfd43b3a7
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/lambda/lambda-const8.C
@@ -0,0 +1,19 @@
+// PR c++/85761
+// { dg-do compile { target c++11 } }
+
+template <typename T>
+void out(const T& value);
+
+struct foo {
+ void bar();
+};
+
+void foo::bar()
+{
+ constexpr int COUNT = 10000;
+ auto run = []() {
+ out(COUNT); // { dg-error "9:not captured" }
+ };
+
+ run();
+}
