Copybara import of the project:

--
7f117fa7a7060b36687e7544e8d7393d14a1fa90 by Yuval Tassa <tassa@google.com>:

Handle clang AST loc nodes with elided 'line' in introspect codegen.

Apple's math.h (included directly by mujoco.h) contains an anonymous union
whose clang-JSON 'loc' lacks the 'line' key (clang elides it when unchanged
from the previous node), crashing AstProcessor._make_anonymous_key with a
KeyError during bindings regeneration on macOS. glibc's math.h has no such
union, so this never bites on Linux.

Fall back to an offset-based key for line-less nodes; these system-header
structs are never referenced by MuJoCo types, so the key only needs to be
unique.

COPYBARA_INTEGRATE_REVIEW=https://github.com/google-deepmind/mujoco/pull/3411 from yuvaltassa:introspect-loc-fallback 7f117fa7a7060b36687e7544e8d7393d14a1fa90
PiperOrigin-RevId: 949626713
Change-Id: I9d99b427885ede18b075db6d4e507aa8bc0d049a

python/mujoco/introspect/codegen/ast_processor.py

@@ -332,9 +332,13 @@ class AstProcessor:
     )
 
   def _make_anonymous_key(self, node: ClangJsonNode) -> str:
-    line = node['loc']['line']
-    col = node['loc']['col']
-    return f'{line}:{col}'
+    loc = node['loc']
+    if 'line' not in loc:
+      # Clang elides 'line' when unchanged from the previous node. This only
+      # occurs for system-header structs never referenced by MuJoCo types, so
+      # the key merely needs to be unique.
+      return f"offset{loc.get('offset')}:{loc.get('col')}"
+    return f"{loc['line']}:{loc['col']}"
 
 
 def _traverse(node, visitor):