commit 39282e1f31f1eda8f67c1aee9232ecfc695f031a
author Olli Etuaho <oetuaho@nvidia.com> Thu Apr 23 15:41:48 2015 +0300
committer Olli Etuaho <oetuaho@nvidia.com> Fri Apr 24 08:45:35 2015 +0000
tree 8f45a63a08ec7e1ceef9485968313a2af4417f93
parent 96e6738830bf9431e41b30f18631a84b35d7ac1a

Disallow length being called on expressions with side effects

ESSL 3.00 definition of expressions does not include calling length on
anything other than array names, so enforce this restriction in the
parser.

TEST=WebGL 2 conformance tests
BUG=angleproject:972

Change-Id: I893d3c468ff21cb419b3239738f2a41834298cf2
Reviewed-on: https://chromium-review.googlesource.com/266992
Reviewed-by: Olli Etuaho <oetuaho@nvidia.com>
Tested-by: Olli Etuaho <oetuaho@nvidia.com>

src/compiler/translator/ParseContext.cpp

diff --git a/src/compiler/translator/ParseContext.cpp b/src/compiler/translator/ParseContext.cpp
index 014a9b2..9b9ca3a 100644
--- a/src/compiler/translator/ParseContext.cpp
+++ b/src/compiler/translator/ParseContext.cpp
@@ -3168,12 +3168,17 @@
         else
         {
             arraySize = typedThis->getArraySize();
-            if (typedThis->hasSideEffects())
+            if (typedThis->getAsSymbolNode() == nullptr)
             {
-                // This code path can be hit with an expression like this:
+                // This code path can be hit with expressions like these:
                 // (a = b).length()
-                // where a and b are both arrays.
-                UNIMPLEMENTED();
+                // (func()).length()
+                // (int[3](0, 1, 2)).length()
+                // ESSL 3.00 section 5.9 defines expressions so that this is not actually a valid expression.
+                // It allows "An array name with the length method applied" in contrast to GLSL 4.4 spec section 5.9
+                // which allows "An array, vector or matrix expression with the length method applied".
+                error(loc, "length can only be called on array names, not on array expressions", "length");
+                recover();
             }
         }
         unionArray->setIConst(arraySize);