Return a program binary size of 0 when the program is not linked.

src/libANGLE/Program.cpp

@@ -1401,6 +1401,11 @@ Error Program::saveBinary(const Context *context,
 
 GLint Program::getBinaryLength(const Context *context) const
 {
+    if (!mLinked)
+    {
+        return 0;
+    }
+
     GLint length;
     Error error = saveBinary(context, nullptr, nullptr, std::numeric_limits<GLint>::max(), &length);
     if (error.isError())

src/tests/gl_tests/ProgramBinaryTest.cpp

@@ -235,6 +235,17 @@ TEST_P(ProgramBinaryTest, CallProgramBinaryBeforeLink)
     ASSERT_GL_NO_ERROR();
 }
 
+// Test that unlinked programs have a binary size of 0
+TEST_P(ProgramBinaryTest, ZeroSizedUnlinkedBinary)
+{
+    ANGLE_SKIP_TEST_IF(!supported());
+
+    ANGLE_GL_EMPTY_PROGRAM(program);
+    GLsizei length = 0;
+    glGetProgramiv(program, GL_PROGRAM_BINARY_LENGTH, &length);
+    ASSERT_EQ(0, length);
+}
+
 // Use this to select which configurations (e.g. which renderer, which GLES major version) these tests should be run against.
 ANGLE_INSTANTIATE_TEST(ProgramBinaryTest,
                        ES2_D3D9(),

src/tests/test_utils/gl_raii.h

@@ -101,6 +101,8 @@ class GLProgram
 
     ~GLProgram() { glDeleteProgram(mHandle); }
 
+    void makeEmpty() { mHandle = glCreateProgram(); }
+
     void makeCompute(const std::string &computeShader)
     {
         mHandle = CompileComputeProgram(computeShader);
@@ -152,6 +154,11 @@ class GLProgram
 };
 }  // namespace priv
 
+#define ANGLE_GL_EMPTY_PROGRAM(name) \
+    priv::GLProgram name;            \
+    name.makeEmpty();                \
+    ASSERT_TRUE(name.valid());
+
 #define ANGLE_GL_PROGRAM(name, vertex, fragment) \
     priv::GLProgram name;                        \
     name.makeRaster(vertex, fragment);           \