From d128a6bbe4b50d1c2d035d4cf59b9ab38f398159 Mon Sep 17 00:00:00 2001
From: Ian Lance Taylor <ian@gcc.gnu.org>
Date: Sat, 19 Feb 2011 04:36:33 +0000
Subject: [PATCH] Don't crash on out of range switch value.

From-SVN: r170305
---
 gcc/go/gofrontend/statements.cc | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/gcc/go/gofrontend/statements.cc b/gcc/go/gofrontend/statements.cc
index bb5a6a09d0b..99ed6653914 100644
--- a/gcc/go/gofrontend/statements.cc
+++ b/gcc/go/gofrontend/statements.cc
@@ -3212,7 +3212,12 @@ Case_clauses::Case_clause::get_constant_tree(Translate_context* context,
 	  mpz_t ival;
 	  mpz_init(ival);
 	  if (!(*p)->integer_constant_value(true, ival, &itype))
-	    gcc_unreachable();
+	    {
+	      // Something went wrong.  This can happen with a
+	      // negative constant and an unsigned switch value.
+	      gcc_assert(saw_errors());
+	      continue;
+	    }
 	  gcc_assert(itype != NULL);
 	  tree type_tree = itype->get_tree(context->gogo());
 	  tree val = Expression::integer_constant_tree(ival, type_tree);
-- 
2.30.2