Add .cmake files and fix LICENSE file path in make_sdist.sh.

Also make minor modifications to Python bindings code for GCC compatibility.

Fixes #191.

PiperOrigin-RevId: 435127640
Change-Id: I8bd3a35bbb2724a24341072ba8df3da4372f83d3

python/mujoco/errors.h

@@ -119,7 +119,12 @@ struct MjErrorIntercepter {
   template <typename Return, typename... Args, typename Callable>
   MUJOCO_ALWAYS_INLINE
   static constexpr auto WrapFunc(Callable&& callable) {
+#if defined(__GNUC__) && !defined(__clang__)
+    // GCC can't inline functions that call setjmp
+    return [callable](Args... args) mutable {
+#else
     return [callable](Args... args) MUJOCO_ALWAYS_INLINE_LAMBDA_MUTABLE {
+#endif
       _mjPRIVATE__set_tls_error_fn(&MjErrorHandler);
 
       // DON'T MIX RAII WITH SETJMP!

python/mujoco/util/crossplatform.h

@@ -25,7 +25,11 @@
     (defined(__GNUC__) && !defined(__clang__))
 #define MUJOCO_ALWAYS_INLINE __attribute__((always_inline))
 #define MUJOCO_ALWAYS_INLINE_LAMBDA MUJOCO_ALWAYS_INLINE
+#if defined(__clang__)
 #define MUJOCO_ALWAYS_INLINE_LAMBDA_MUTABLE MUJOCO_ALWAYS_INLINE_LAMBDA mutable
+#else
+#define MUJOCO_ALWAYS_INLINE_LAMBDA_MUTABLE mutable MUJOCO_ALWAYS_INLINE_LAMBDA
+#endif
 #elif defined(_MSC_VER)
 #define MUJOCO_ALWAYS_INLINE __forceinline
 #if _MSC_VER >= 1927 && _MSVC_LANG >= 202002L