[cfe-dev] [PATCH] MS compatibility flag implies delayed parsing

[Francois Pichet]

On Thu, Nov 17, 2011 at 2:46 PM,  <dawn at burble.org> wrote:
> Please let this be a separate option from the ms-mode option.  See comment
> below.
>
> On Sat, Nov 12, 2011 at 03:08:43PM -0600, Aaron Ballman wrote:
>> On Tue, Nov 8, 2011 at 8:51 PM, Douglas Gregor <dgregor at apple.com> wrote:
>> >
>> > On Nov 8, 2011, at 6:56 AM, Aaron Ballman wrote:
>> >
>> >> On Mon, Nov 7, 2011 at 4:55 PM, Eli Friedman <eli.friedman at gmail.com> wrote:
>> >>> I don't see why the changes to lib/Frontend/CompilerInvocation.cpp and
>> >>> include/clang/Driver/CC1Options.td are necessary.  The changes to
>> >>> lib/Driver/Tools.cpp look fine.
>> >>
>> >> I'm not certain I understand why the two are separate from one
>> >> another.  Can you give me a quite education on the topic?
>> >>
>> >> On Mon, Nov 7, 2011 at 5:02 PM, Francois Pichet <pichet2000 at gmail.com> wrote:
>> >>> How about we remove --fdelayed-template-parsing altogether and check
>> >>> for fms-compatibility to do late template parsing?
>> >>>
>> >>> Anybody else needs delayed template parsing without microsoft compatibility?
>
> We do!  And we don't want them to be tied to ms-mode, because we want to
> be able to set ms-mode (to get ms language extensions) but allow 2-phase
> lookup by default.  For legacy code however, we want to allow users to
> be able to disable 2-phase lookup.

Just to be clear, -fdelayed-template-parsing doesn't disable 2-phase
lookup. It just delay phase 1 lookup until the end of the translation
unit with the effect of making more symbols available then. In
practice that's enough to get very good compatibility with MSVC
template code.