Craig Ringer <[email protected]> writes:
> Example here:
> https://github.com/ringerc/scrapcode/tree/master/c/clang_return_stack_checks
> So I find that actually, the __attribute__((callback(fn)) approach is
> unnecessary for the purpose proposed.
I tested this by injecting some faults of the described sort.
diff --git a/src/backend/commands/copy.c b/src/backend/commands/copy.c
index db7d24a511..eaf7716816 100644
--- a/src/backend/commands/copy.c
+++ b/src/backend/commands/copy.c
@@ -3025,6 +3025,8 @@ CopyFrom(CopyState cstate)
myslot =
CopyMultiInsertInfoNextFreeSlot(&multiInsertInfo,
resultRelInfo);
+ if (!myslot)
+ return 0;
}
/*
leads to
/home/tgl/pgsql/src/backend/commands/copy.c:3029:6: warning: Address of stack
memory associated with local variable 'errcallback' is still referred to by the
global variable 'error_context_stack' upon returning to the caller. This will
be a dangling reference
return 0;
^~~~~~~~
So that's good. However, a similar experiment with returning from inside
a PG_TRY does *not* produce a warning. I suspect maybe the compiler
throws up its hands when it sees sigsetjmp?
(These results from clang 10.0.0 on Fedora 32.)
regards, tom lane
