+/* We have to check for a fairly pathological case. The operands of function
+ nested function are to be interpreted in the context of the enclosing
+ function. So if any are variably-sized, they will get remapped when the
+ enclosing function is inlined. But that remapping would also have to be
+ done in the types of the PARM_DECLs of the nested function, meaning the
+ argument types of that function will disagree with the arguments in the
+ calls to that function. So we'd either have to make a copy of the nested
+ function corresponding to each time the enclosing function was inlined or
+ add a VIEW_CONVERT_EXPR to each such operand for each call to the nested
+ function. The former is not practical. The latter would still require
+ detecting this case to know when to add the conversions. So, for now at
+ least, we don't inline such an enclosing function.
+
+ We have to do that check recursively, so here return indicating whether
+ FNDECL has such a nested function. ORIG_FN is the function we were
+ trying to inline to use for checking whether any argument is variably
+ modified by anything in it.
+
+ It would be better to do this in tree-inline.c so that we could give
+ the appropriate warning for why a function can't be inlined, but that's
+ too late since the nesting structure has already been flattened and
+ adding a flag just to record this fact seems a waste of a flag. */
+
+static bool
+check_for_nested_with_variably_modified (tree fndecl, tree orig_fndecl)
+{
+ struct cgraph_node *cgn = cgraph_node (fndecl);
+ tree arg;
+
+ for (cgn = cgn->nested; cgn ; cgn = cgn->next_nested)
+ {
+ for (arg = DECL_ARGUMENTS (cgn->decl); arg; arg = TREE_CHAIN (arg))
+ if (variably_modified_type_p (TREE_TYPE (arg), 0), orig_fndecl)
+ return true;
+
+ if (check_for_nested_with_variably_modified (cgn->decl, orig_fndecl))
+ return true;
+ }
+
+ return false;
+}
+