Re: [RFC 5/8] static-analyzer: Enforce coroutine_fn restrictions on function pointers

[Víctor Colombo]

On 02/07/2022 08:33, Alberto Faria wrote:

Alberto, hello. I was testing this patch as follows:

./static-analyzer.py build target/ppc/mmu-hash64.c

<snip>

@@ -627,9 +744,31 @@ def is_coroutine_fn(node: Cursor) -> bool:
          else:
              break

-    return node.kind == CursorKind.FUNCTION_DECL and is_annotated_with(
-        node, "coroutine_fn"
-    )
+    if node.kind in [CursorKind.DECL_REF_EXPR, CursorKind.MEMBER_REF_EXPR]:
+        node = node.referenced
+
+    # ---
+
+    if node.kind == CursorKind.FUNCTION_DECL:

And I receive an exception on the line above saying that node is of type
NoneType. Seems that `node = node.referenced` is setting `node` to None
in this case.

I was unable to understand the root cause of it. Is this an incorrect
usage of the tool from my part? Full error message below

Traceback (most recent call last):
  File "./static-analyzer.py", line 327, in analyze_translation_unit
    checker(tu, context.absolute_path, log)
  File "./static-analyzer.py", line 613, in check_coroutine_pointers
    and is_coroutine_fn(right)
  File "./static-analyzer.py", line 781, in is_coroutine_fn
    if node.kind == CursorKind.FUNCTION_DECL:
AttributeError: 'NoneType' object has no attribute 'kind'

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/usr/lib/python3.8/multiprocessing/pool.py", line 125, in worker
    result = (True, func(*args, **kwds))
  File "/usr/lib/python3.8/multiprocessing/pool.py", line 48, in mapstar
    return list(map(*args))
  File "./static-analyzer.py", line 329, in analyze_translation_unit
    raise RuntimeError(f"Error analyzing {relative_path}") from e
RuntimeError: Error analyzing target/ppc/mmu-hash64.c
"""

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "./static-analyzer.py", line 893, in <module>
    main()
  File "./static-analyzer.py", line 123, in main
    analyze_translation_units(args, contexts)
  File "./static-analyzer.py", line 240, in analyze_translation_units
    results = pool.map(analyze_translation_unit, contexts)
  File "/usr/lib/python3.8/multiprocessing/pool.py", line 364, in map
    return self._map_async(func, iterable, mapstar, chunksize).get()
  File "/usr/lib/python3.8/multiprocessing/pool.py", line 771, in get
    raise self._value
RuntimeError: Error analyzing target/ppc/mmu-hash64.c

> +        return is_annotated_with(node, "coroutine_fn")

+
+    if node.kind in [
+        CursorKind.FIELD_DECL,
+        CursorKind.VAR_DECL,
+        CursorKind.PARM_DECL,
+    ]:
+
+        if is_annotated_with(node, "coroutine_fn"):
+            return True
+
+        # TODO: If type is typedef or pointer to typedef, follow typedef.
+
+        return False
+
+    if node.kind == CursorKind.TYPEDEF_DECL:
+        return is_annotated_with(node, "coroutine_fn")
+
+    return False

Best regards,

--
Víctor Cora Colombo
Instituto de Pesquisas ELDORADO
Aviso Legal - Disclaimer <https://www.eldorado.org.br/disclaimer.html>