From 7228b01c2dce40a6a581bb413d605e0f76cab6eb Mon Sep 17 00:00:00 2001
From: Swung0x48 <swung0x48@outlook.com>
Date: Thu, 6 Nov 2025 23:21:23 +0800
Subject: [PATCH] [Fix] (GLImpl/Program, MG_Backend/DirectGLES): guard against
 not linked program object

---
 MobileGL/MG_Backend/DirectGLES/DirectGLES.cpp  | 4 ++--
 MobileGL/MG_Impl/GLImpl/Program/GL_Program.cpp | 7 ++++---
 2 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/MobileGL/MG_Backend/DirectGLES/DirectGLES.cpp b/MobileGL/MG_Backend/DirectGLES/DirectGLES.cpp
index d3af7173..58c2b858 100644
--- a/MobileGL/MG_Backend/DirectGLES/DirectGLES.cpp
+++ b/MobileGL/MG_Backend/DirectGLES/DirectGLES.cpp
@@ -223,7 +223,7 @@ namespace MobileGL::MG_Backend::DirectGLES {
     namespace PrgramImpl {
         void SyncCurrentProgram() {
             auto currentProgram = MG_State::pGLContext->GetCurrentProgram();
-            if (!currentProgram) {
+            if (!currentProgram || !currentProgram->GetLinkStatus()) {
                 MG_External::GLES::glUseProgram(0);
                 return;
             }
@@ -311,7 +311,7 @@ namespace MobileGL::MG_Backend::DirectGLES {
         MG_External::GLES::glActiveTexture(GL_TEXTURE0 + originalActiveUnit);
 
         const auto& currentProgram = MG_State::pGLContext->GetCurrentProgram();
-        if (currentProgram) {
+        if (currentProgram && currentProgram->GetLinkStatus()) {
             const auto& backendProgramIt = PrgramImpl::g_backendProgramObjects.find(currentProgram);
             if (backendProgramIt != PrgramImpl::g_backendProgramObjects.end()) {
                 backendProgramIt->second->Use();
diff --git a/MobileGL/MG_Impl/GLImpl/Program/GL_Program.cpp b/MobileGL/MG_Impl/GLImpl/Program/GL_Program.cpp
index 8031d294..afb209fd 100644
--- a/MobileGL/MG_Impl/GLImpl/Program/GL_Program.cpp
+++ b/MobileGL/MG_Impl/GLImpl/Program/GL_Program.cpp
@@ -158,7 +158,7 @@ namespace MobileGL {
                 return;
             }
             auto programObject = TryToGetProgramObject(program);
-            if (!programObject) return;
+            if (!programObject || !programObject->GetLinkStatus()) return;
             auto attribCount = programObject->GetActiveAttributesCount();
             if (index >= attribCount) {
                 MG_State::pGLContext->RecordError(
@@ -183,7 +183,7 @@ namespace MobileGL {
                 return;
             }
             auto programObject = TryToGetProgramObject(program);
-            if (!programObject) return;
+            if (!programObject || !programObject->GetLinkStatus()) return;
             auto uniformCount = programObject->GetUniformCount();
             if (index >= uniformCount) {
                 MG_State::pGLContext->RecordError(
@@ -438,6 +438,7 @@ namespace MobileGL {
         void LinkProgram_State(GLuint program) {
             auto programObject = TryToGetProgramObject(program);
             if (!programObject) return;
+            MGLOG_D("%s: linking program %d", __func__, program);
             programObject->Link();
         }
 
@@ -827,7 +828,7 @@ namespace MobileGL {
         }
 
         void ValidateProgram_State(GLuint program) {
-            THROW_UNIMPL_EXCEPTION;
+//            THROW_UNIMPL_EXCEPTION;
         }
 
         void AttachShader(GLuint program, GLuint shader) {