[cfe-dev] patch: keep llvm module consistent during compilationpatch: keep llvm module consistent during compilation
Chris Lattner
clattner at apple.com
Mon Jul 21 15:23:33 PDT 2008
On Jul 18, 2008, at 10:40 AM, Daniel Dunbar wrote:
> The attached patch creates dummy bodies for functions with internal
> linkage
> when they are created and replaces them when the definition is
> compiled. This
> helps ensure that the module is in a consistent state after
> processing each top
> level declaration and prevents crashes in the verifier on malformed
> inputs. See
> test case.
This is a somewhat interesting issue. As you know, I strongly believe
in having clang keep its module consistent where possible. There are
two possible solutions to this issue: either give static forward decls
a body or not mark them internal.
Of the two, I prefer the later because it doesn't require creating
blocks and instructions only to throw them away later. What do you
think?
> This should probably be documented at another level than just a code
> comment
> but I'm not sure where...
Yeah, clang as a whole is not well documented from the high-level
perspective. We have an internals document but it is pretty thin.
> Note that this introduces a problem that modules which declare
> static functions
> but do not define them will compile (and link!) but this is a bug in
> sema. Maybe
> we should still be tracking them though to make sure none slip
> through to the
> outside. This requires CG having some way of knowing when the module
> is done.
I think we should reject this in sema.
> p.s. Comments appreciated on a simpler way to write the DG test I
want (checking
Does it work to use "-emit-llvm -verify" and slap an "expected-error"
note on the line that an error is expected?
-Chris
More information about the cfe-dev
mailing list