commit b081e78b0a0f5ab6ee4633c9fd3a1199d52e2dd2
author Corentin Wallez <cwallez@chromium.org> Mon Jul 20 05:40:04 2015 -0700
committer Corentin Wallez <cwallez@chromium.org> Mon Jul 20 17:01:12 2015 +0000
tree c4ac664c5bbd1ea24ae4d9a261f929d100744623
parent a455824c69b80f036a9e7a69517e561eb65d481d

Compiler: avoid an undefined behavior when using erase-remove

Using that idiom on an empty vector results in an undefined behavior
that I have seen cause a vector to get length -1 with clang 3.6 on
Linux.

BUG=

Change-Id: I3bb8d8884efa29a17672b458263067644dbf0fec
Reviewed-on: https://chromium-review.googlesource.com/286740
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Tested-by: Corentin Wallez <cwallez@chromium.org>

src/compiler/translator/Compiler.cpp

diff --git a/src/compiler/translator/Compiler.cpp b/src/compiler/translator/Compiler.cpp
index cd571f8..990863a 100644
--- a/src/compiler/translator/Compiler.cpp
+++ b/src/compiler/translator/Compiler.cpp
@@ -649,7 +649,11 @@
 
     UnusedPredicate isUnused(&mCallDag, &functionMetadata);
     TIntermSequence *sequence = rootNode->getSequence();
-    sequence->erase(std::remove_if(sequence->begin(), sequence->end(), isUnused), sequence->end());
+
+    if (!sequence->empty())
+    {
+        sequence->erase(std::remove_if(sequence->begin(), sequence->end(), isUnused), sequence->end());
+    }
 
     return true;
 }