Suppress more GCC warnings.

Add workaround of `maybe-uninitialized` on gcc.

Author: syoyo

src/crate-reader.cc

@@ -2795,7 +2795,7 @@ bool CrateReader::UnpackValueRep(const crate::ValueRep &rep,
 
         CHECK_MEMORY_USAGE(sizeof(double));
 
-        double v;
+        double v{0.0};
         if (!_sr->read_double(&v)) {
           PUSH_ERROR("Failed to read Double value.");
           return false;

src/image-util.cc

@@ -16,6 +16,7 @@
 #pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wunused-variable"
 #pragma GCC diagnostic ignored "-Wunused-function"
+#pragma GCC diagnostic ignored "-Warray-bounds"
 #endif
 
 #if !defined(TINYUSDZ_NO_STB_IMAGE_RESIZE_IMPLEMENTATION)

src/linear-algebra.cc

@@ -51,8 +51,9 @@ value::quatf slerp(const value::quatf &a, const value::quatf &b, const float t)
 
   qret = linalg::slerp(qa, qb, t);
 
-  
-  return *(reinterpret_cast<value::quatf *>(&qret));
+  value::quatf ret;
+  memcpy(&ret, reinterpret_cast<value::quatf *>(&qret), sizeof(float) * 4);
+  return ret;
 }
 
 value::quatd slerp(const value::quatd &a, const value::quatd &b, const double t) {
@@ -65,9 +66,11 @@ value::quatd slerp(const value::quatd &a, const value::quatd &b, const double t)
   memcpy(reinterpret_cast<value::quatd *>(&qb), &b, sizeof(double) * 4);
 
   qret = linalg::slerp(qa, qb, t);
-  
-  return *(reinterpret_cast<value::quatd *>(&qret));
 
+  value::quatd ret;
+  memcpy(&ret, reinterpret_cast<value::quatd *>(&qret), sizeof(double) * 4);
+  return ret;
+  
 }
 
 float vlength(const value::float3 &a) {

src/stream-reader.hh

@@ -293,7 +293,7 @@ class StreamReader {
       return false;
     }
 
-    float value;
+    float value{};
     if (!read4(reinterpret_cast<int *>(&value))) {
       return false;
     }
@@ -308,7 +308,7 @@ class StreamReader {
       return false;
     }
 
-    double value;
+    double value{};
     if (!read8(reinterpret_cast<uint64_t *>(&value))) {
       return false;
     }

src/tydra/render-data.hh

@@ -1060,10 +1060,18 @@ struct UDIMTexture {
   std::unordered_map<uint32_t, int32_t> imageTileIds;
 };
 
+// workaround for GCC
+#if defined(__GNUC__) && !defined(__clang__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wmaybe-uninitialized"
+#endif
+
 // T or TextureId
 template <typename T>
-struct ShaderParam {
-  ShaderParam(const T &t) { value = t; }
+class ShaderParam {
+ public:
+  ShaderParam() = default;
+  ShaderParam(const T &t) : value(t) { }
 
   bool is_texture() const { return texture_id >= 0; }
 
@@ -1078,12 +1086,14 @@ struct ShaderParam {
     memcpy(&value, &val, sizeof(T));
   }
 
-  T value;
+ //private:
+  T value{};
   int32_t texture_id{-1};  // negative = invalid
 };
 
 // UsdPreviewSurface
-struct PreviewSurfaceShader {
+class PreviewSurfaceShader {
+ public:
   bool useSpecularWorkflow{false};
 
   ShaderParam<vec3> diffuseColor{{0.18f, 0.18f, 0.18f}};
@@ -1103,6 +1113,10 @@ struct PreviewSurfaceShader {
   uint64_t handle{0};  // Handle ID for Graphics API. 0 = invalid
 };
 
+#if defined(__GNUC__) && !defined(__clang__)
+#pragma GCC diagnostic pop
+#endif
+
 // Material + Shader
 struct RenderMaterial {
   std::string name;  // elementName in USD (e.g. "pbrMat")