[cfe-dev] [PATCH] Preserve -fretain-comments-from-system-headers in modules

[Argyrios Kyrtzidis]

Looks good but making the flag part of the module hash requires a couple more changes.

See my commit r180635 where I do the same for the detailed-preprocessing-record flag.
Basically a PCH created with modules is pointing to the module file path, and the module hash is part of the path, so it is important the the module hash between the originating invocation and the PCH agree. That commit makes the flag significant when modules are enabled and rejects a PCH that didn't enable the flag.

Also the flag should be serialized (this is shown in r180635 as well).

On Jan 8, 2014, at 4:56 PM, Ben Langmuir <blangmuir at apple.com> wrote:

> This patch preserves the setting of -fretain-comments-from-system-headers when building, storing and loading modules, which allows code completion to pick up documentation comments from system headers.<module-system-header-comments.patch>