[Fix] (Pipe): skip the location tables a failed relink cleared when emitting program bindings

MobileGL/MG_Impl/Pipe/ProgramEmit.h

@@ -344,7 +344,7 @@ namespace MobileGL::MG_Pipe {
             for (Uint loc = 0; loc <= maxUniformLoc; ++loc) {
                 // The same guard CacheResourceLocations uses one level down: a location with no
                 // uniform behind it has an empty name and must not index the type tables.
-                if (program.GetUniformName(loc).empty()) continue;
+                if (!program.HasUniformLocationTables(loc) || program.GetUniformName(loc).empty()) continue;
                 const Int unit = program.GetUniformSamplerOrImageUnitIndex(loc);
                 if (unit < 0) continue;
                 if (m_samplerUnits.size() >= kMGPipeMaxProgramSamplerUnits) {

MobileGL/MG_State/GLState/ProgramState/ProgramObject.h

@@ -895,6 +895,16 @@ namespace MobileGL::MG_State::GLState {
             return Artifacts().uniformSamplerOrImageUnitIndex[location];
         }
 
+        // True when |location| indexes the per-location tables. GetMaxUniformLocation() alone
+        // cannot say so: a link that fails clears the tables and leaves it at 0, which reads
+        // the same as "one location", while the program's previous executable - and its
+        // pipe handle - stays in use (GL 4.6 core 7.3).
+        Bool HasUniformLocationTables(Uint location) const {
+            const auto& artifacts = Artifacts();
+            return location < artifacts.uniformIndexInTProgram.size() &&
+                   location < artifacts.uniformSamplerOrImageUnitIndex.size();
+        }
+
         Bool GetDeleteStatus() const { return m_deleteStatus; }
         Bool GetLinkStatus() const { return Artifacts().linkStatus; }
         // GL_PROGRAM_BINARY_RETRIEVABLE_HINT. MobileGL exposes no program binary format

MobileGL/MG_Test/Pipe/ProgramEmitTest.cpp

@@ -919,6 +919,35 @@ void main() { gl_Position = u_a + u_b + u_c + u_d; }
         }
     }
 
+    // KHR-GL46.sepshaderobjs.StateInteraction crashed the client here. A relink that fails
+    // clears the per-location tables but leaves GetMaxUniformLocation() at 0, while the
+    // previous executable - and the CSO naming it - stays in use, so the next validate point
+    // walked location 0 straight off an empty array.
+    TEST(ProgramEmit, BindingsOfAProgramWhoseRelinkFailedReadNoLocationTables) {
+        EmitterScope scope;
+        const GLuint name = MakeVsFsProgram();
+        const SharedPtr<ProgramObject>& program = Ctx().GetProgramObject(name);
+        ASSERT_TRUE(program);
+        Uint64 bytes = 0;
+        const MGPipeHandle cso = Emitter().AcquireShaderCso(*program, bytes);
+        ASSERT_FALSE(MGPipeHandleIsNull(cso));
+        EXPECT_TRUE(program->HasUniformLocationTables(0)) << "a linked program must own its tables";
+
+        Vector<GLuint> attached;
+        for (const auto& shader : program->GetAttachedShaders()) attached.push_back(shader->GetExternalIndex());
+        for (const GLuint shader : attached) GL::DetachShader(name, shader);
+        GL::LinkProgram(name);
+        GLint linked = GL_TRUE;
+        GL::GetProgramiv(name, GL_LINK_STATUS, &linked);
+        ASSERT_EQ(linked, GL_FALSE) << "a program with no shaders must fail to link";
+        ASSERT_FALSE(program->HasUniformLocationTables(0)) << "the failed link must clear the tables";
+
+        const Uint64 before = Emitter().ProgramBindingsSetCount();
+        Emitter().EmitProgramBindings(*program, cso);
+        EXPECT_EQ(Emitter().ProgramBindingsSetCount(), before + 1);
+        EXPECT_EQ(Emitter().LastProgramBindings().SamplerUnitCount, 0u);
+    }
+
     // The applier's half: whole-set replacement in all three tails, and a re-issued create
     // drops them because they are INDICES INTO the archive it has just replaced.
     TEST(ProgramEmit, TheThreeBindingTailsAreWholeSetsAndAReIssuedCreateDropsThem) {