diff --git a/src/gui/opengl/qopengltexturehelper.cpp b/src/gui/opengl/qopengltexturehelper.cpp
index 4da9b3f1641..97ae4df8047 100644
--- a/src/gui/opengl/qopengltexturehelper.cpp
+++ b/src/gui/opengl/qopengltexturehelper.cpp
@@ -119,15 +119,6 @@ QOpenGLTextureHelper::QOpenGLTextureHelper(QOpenGLContext *context)
         CompressedTextureImage1D = &QOpenGLTextureHelper::qt_CompressedTextureImage1D;
         CompressedTextureImage2D = &QOpenGLTextureHelper::qt_CompressedTextureImage2D;
         CompressedTextureImage3D = &QOpenGLTextureHelper::qt_CompressedTextureImage3D;
-#if defined(QT_OPENGL_ES_2)
-        if (context->hasExtension(QByteArrayLiteral("GL_OES_texture_3D"))) {
-            TexImage3D = reinterpret_cast<void (QOPENGLF_APIENTRYP)(GLenum, GLint, GLint, GLsizei, GLsizei, GLsizei, GLint, GLenum, GLenum, const GLvoid*)>(context->getProcAddress(QByteArrayLiteral("glTexImage3DOES")));
-            TexSubImage3D = reinterpret_cast<void (QOPENGLF_APIENTRYP)(GLenum, GLint, GLint, GLint, GLint, GLsizei, GLsizei, GLsizei, GLenum, GLenum, const GLvoid*)>(context->getProcAddress(QByteArrayLiteral("glTexSubImage3DOES")));
-            CompressedTexImage3D = reinterpret_cast<void (QOPENGLF_APIENTRYP)(GLenum, GLint, GLenum, GLsizei, GLsizei, GLsizei, GLint, GLsizei, const GLvoid*)>(context->getProcAddress(QByteArrayLiteral("glCompressedTexImage3DOES")));
-            CompressedTexSubImage3D = reinterpret_cast<void (QOPENGLF_APIENTRYP)(GLenum, GLint, GLint, GLint, GLint, GLsizei, GLsizei, GLsizei, GLenum, GLsizei, const GLvoid*)>(context->getProcAddress(QByteArrayLiteral("glCompressedTexSubImage3DOES")));
-        }
-#endif
-
 #if !defined(QT_OPENGL_ES_2)
     }
 #endif
@@ -200,18 +191,30 @@ QOpenGLTextureHelper::QOpenGLTextureHelper(QOpenGLContext *context)
     TexSubImage1D = reinterpret_cast<void (QOPENGLF_APIENTRYP)(GLenum , GLint , GLint , GLsizei , GLenum , GLenum , const GLvoid *)>(context->getProcAddress(QByteArrayLiteral("glTexSubImage1D")));
 #endif
 
-    // OpenGL 1.2
-    TexImage3D = reinterpret_cast<void (QOPENGLF_APIENTRYP)(GLenum , GLint , GLint , GLsizei , GLsizei , GLsizei , GLint , GLenum , GLenum , const GLvoid *)>(context->getProcAddress(QByteArrayLiteral("glTexImage3D")));
-    TexSubImage3D = reinterpret_cast<void (QOPENGLF_APIENTRYP)(GLenum , GLint , GLint , GLint , GLint , GLsizei , GLsizei , GLsizei , GLenum , GLenum , const GLvoid *)>(context->getProcAddress(QByteArrayLiteral("glTexSubImage3D")));
+#if defined(QT_OPENGL_ES_2)
+    if (context->hasExtension(QByteArrayLiteral("GL_OES_texture_3D"))) {
+        TexImage3D = reinterpret_cast<void (QOPENGLF_APIENTRYP)(GLenum, GLint, GLint, GLsizei, GLsizei, GLsizei, GLint, GLenum, GLenum, const GLvoid*)>(context->getProcAddress(QByteArrayLiteral("glTexImage3DOES")));
+        TexSubImage3D = reinterpret_cast<void (QOPENGLF_APIENTRYP)(GLenum, GLint, GLint, GLint, GLint, GLsizei, GLsizei, GLsizei, GLenum, GLenum, const GLvoid*)>(context->getProcAddress(QByteArrayLiteral("glTexSubImage3DOES")));
+        CompressedTexImage3D = reinterpret_cast<void (QOPENGLF_APIENTRYP)(GLenum, GLint, GLenum, GLsizei, GLsizei, GLsizei, GLint, GLsizei, const GLvoid*)>(context->getProcAddress(QByteArrayLiteral("glCompressedTexImage3DOES")));
+        CompressedTexSubImage3D = reinterpret_cast<void (QOPENGLF_APIENTRYP)(GLenum, GLint, GLint, GLint, GLint, GLsizei, GLsizei, GLsizei, GLenum, GLsizei, const GLvoid*)>(context->getProcAddress(QByteArrayLiteral("glCompressedTexSubImage3DOES")));
+    } else
+#endif
+    {
+        // OpenGL 1.2
+        TexImage3D = reinterpret_cast<void (QOPENGLF_APIENTRYP)(GLenum , GLint , GLint , GLsizei , GLsizei , GLsizei , GLint , GLenum , GLenum , const GLvoid *)>(context->getProcAddress(QByteArrayLiteral("glTexImage3D")));
+        TexSubImage3D = reinterpret_cast<void (QOPENGLF_APIENTRYP)(GLenum , GLint , GLint , GLint , GLint , GLsizei , GLsizei , GLsizei , GLenum , GLenum , const GLvoid *)>(context->getProcAddress(QByteArrayLiteral("glTexSubImage3D")));
+
+        // OpenGL 1.3
+        CompressedTexImage3D = reinterpret_cast<void (QOPENGLF_APIENTRYP)(GLenum , GLint , GLenum , GLsizei , GLsizei , GLsizei , GLint , GLsizei , const GLvoid *)>(context->getProcAddress(QByteArrayLiteral("glCompressedTexImage3D")));
+        CompressedTexSubImage3D = reinterpret_cast<void (QOPENGLF_APIENTRYP)(GLenum , GLint , GLint , GLint , GLint , GLsizei , GLsizei , GLsizei , GLenum , GLsizei , const GLvoid *)>(context->getProcAddress(QByteArrayLiteral("glCompressedTexSubImage3D")));
+    }
 
     // OpenGL 1.3
     GetCompressedTexImage = reinterpret_cast<void (QOPENGLF_APIENTRYP)(GLenum , GLint , GLvoid *)>(context->getProcAddress(QByteArrayLiteral("glGetCompressedTexImage")));
     CompressedTexSubImage1D = reinterpret_cast<void (QOPENGLF_APIENTRYP)(GLenum , GLint , GLint , GLsizei , GLenum , GLsizei , const GLvoid *)>(context->getProcAddress(QByteArrayLiteral("glCompressedTexSubImage1D")));
     CompressedTexSubImage2D = reinterpret_cast<void (QOPENGLF_APIENTRYP)(GLenum , GLint , GLint , GLint , GLsizei , GLsizei , GLenum , GLsizei , const GLvoid *)>(context->getProcAddress(QByteArrayLiteral("glCompressedTexSubImage2D")));
-    CompressedTexSubImage3D = reinterpret_cast<void (QOPENGLF_APIENTRYP)(GLenum , GLint , GLint , GLint , GLint , GLsizei , GLsizei , GLsizei , GLenum , GLsizei , const GLvoid *)>(context->getProcAddress(QByteArrayLiteral("glCompressedTexSubImage3D")));
     CompressedTexImage1D = reinterpret_cast<void (QOPENGLF_APIENTRYP)(GLenum , GLint , GLenum , GLsizei , GLint , GLsizei , const GLvoid *)>(context->getProcAddress(QByteArrayLiteral("glCompressedTexImage1D")));
     CompressedTexImage2D = reinterpret_cast<void (QOPENGLF_APIENTRYP)(GLenum , GLint , GLenum , GLsizei , GLsizei , GLint , GLsizei , const GLvoid *)>(context->getProcAddress(QByteArrayLiteral("glCompressedTexImage2D")));
-    CompressedTexImage3D = reinterpret_cast<void (QOPENGLF_APIENTRYP)(GLenum , GLint , GLenum , GLsizei , GLsizei , GLsizei , GLint , GLsizei , const GLvoid *)>(context->getProcAddress(QByteArrayLiteral("glCompressedTexImage3D")));
     ActiveTexture = reinterpret_cast<void (QOPENGLF_APIENTRYP)(GLenum )>(context->getProcAddress(QByteArrayLiteral("glActiveTexture")));
 
     // OpenGL 3.0