Validate uniforms and attributes name conflicts when linking

src/libANGLE/Program.cpp

@@ -727,6 +727,11 @@ Error Program::link(const gl::Context *context)
             return NoError();
         }
 
+        if (!linkValidateGlobalNames(context, mInfoLog))
+        {
+            return NoError();
+        }
+
         const auto &mergedVaryings = getMergedVaryings(context);
 
         if (!linkValidateTransformFeedback(context, mInfoLog, mergedVaryings, caps))
@@ -2386,6 +2391,36 @@ bool Program::linkValidateTransformFeedback(const gl::Context *context,
     return true;
 }
 
+bool Program::linkValidateGlobalNames(const Context *context, InfoLog &infoLog) const
+{
+    const std::vector<sh::Uniform> &vertexUniforms =
+        mState.mAttachedVertexShader->getUniforms(context);
+    const std::vector<sh::Uniform> &fragmentUniforms =
+        mState.mAttachedFragmentShader->getUniforms(context);
+    const std::vector<sh::Attribute> &attributes =
+        mState.mAttachedVertexShader->getActiveAttributes(context);
+    for (const auto &attrib : attributes)
+    {
+        for (const auto &uniform : vertexUniforms)
+        {
+            if (uniform.name == attrib.name)
+            {
+                infoLog << "Name conflicts between a uniform and an attribute: " << attrib.name;
+                return false;
+            }
+        }
+        for (const auto &uniform : fragmentUniforms)
+        {
+            if (uniform.name == attrib.name)
+            {
+                infoLog << "Name conflicts between a uniform and an attribute: " << attrib.name;
+                return false;
+            }
+        }
+    }
+    return true;
+}
+
 void Program::gatherTransformFeedbackVaryings(const Program::MergedVaryings &varyings)
 {
     // Gather the linked varyings that are used for transform feedback, they should all exist.

src/libANGLE/Program.h

@@ -566,6 +566,7 @@ class Program final : angle::NonCopyable, public LabeledObject
                                        InfoLog &infoLog,
                                        const MergedVaryings &linkedVaryings,
                                        const Caps &caps) const;
+    bool linkValidateGlobalNames(const Context *context, InfoLog &infoLog) const;
 
     void gatherTransformFeedbackVaryings(const MergedVaryings &varyings);
 

src/tests/gl_tests/WebGLCompatibilityTest.cpp

@@ -1511,6 +1511,28 @@ TEST_P(WebGLCompatibilityTest, BuiltInInvariant)
     EXPECT_EQ(0u, program);
 }
 
+// Tests global namespace conflicts between uniforms and attributes.
+// Based on WebGL test conformance/glsl/misc/shaders-with-name-conflicts.html.
+TEST_P(WebGLCompatibilityTest, GlobalNamesConflict)
+{
+    const std::string vertexShader =
+        "attribute vec4 foo;\n"
+        "void main()\n"
+        "{\n"
+        "    gl_Position = foo;\n"
+        "}";
+    const std::string fragmentShader =
+        "precision mediump float;\n"
+        "uniform vec4 foo;\n"
+        "void main()\n"
+        "{\n"
+        "    gl_FragColor = foo;\n"
+        "}";
+
+    GLuint program = CompileProgram(vertexShader, fragmentShader);
+    EXPECT_EQ(0u, program);
+}
+
 // Test dimension and image size validation of compressed textures
 TEST_P(WebGLCompatibilityTest, CompressedTextureS3TC)
 {