[cfe-dev] PCH: separation from source header

[Sebastian Redl]

On Sep 23, 2010, at 7:42 AM, Douglas Gregor wrote:

> 
> On Sep 23, 2010, at 3:17 AM, Argyrios Kyrtzidis wrote:
>> I think we should change the cannot-use-PCH errors to warnings and fallback to the source header, and maybe add a command-line option to enable the current behavior (hard errors when PCH can't be used).
>> Anyone have an objection about this ?
> 
> We explicitly didn't do this because the build system should never be telling Clang to use a PCH file if it isn't correct.  However, so long as it's a remappable warning, it would be okay to make this change.

Note that I'm not quite sure that our current PCH code can handle this. I've been modifying it under the assumption that failed PCH always means failed compilation, and I might have unknowingly done something that relies on it.

Sebastian