Fix potential undefined behavior when converting to and from glm types from LLVector3/4 and fall back mul_mat4_vec3 to scalar implementation to attempt crash mitigation (#3339)

1 files changed, 13 insertions, 0 deletions

diff --git a/indra/llmath/llvector4a.h b/indra/llmath/llvector4a.h
index 8ef560dadf..4004852e06 100644
--- a/indra/llmath/llvector4a.h
+++ b/indra/llmath/llvector4a.h
@@ -33,6 +33,9 @@ class LLRotation;
 #include <assert.h>
 #include "llpreprocessor.h"
 #include "llmemory.h"
+#include "glm/vec3.hpp"
+#include "glm/vec4.hpp"
+#include "glm/gtc/type_ptr.hpp"
 
 ///////////////////////////////////
 // FIRST TIME USERS PLEASE READ
@@ -364,6 +367,16 @@ public:
 
     inline operator LLQuad() const;
 
+    explicit inline operator glm::vec3() const
+    {
+        return glm::make_vec3(getF32ptr());
+    };
+
+    explicit inline operator glm::vec4() const
+    {
+        return glm::make_vec4(getF32ptr());
+    };
+
 private:
     LLQuad mQ{};
 };