[Bug preprocessor/55115] [>=4.5.0 regression] missing headers as fatal breaks cproto logic

["pierre.poissinger at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55115

--- Comment #10 from Pierre Poissinger <pierre.poissinger at gmail dot com> 2012-10-29 15:24:04 UTC ---
No issues - made me smile :-)

I know there are way around, just first tried the "upstream" path to see if
there are any "quick" ways to ensure that we won't run into issues when we will
finally use a more recent gcc.

This was mostly due to thing in gcc doc that seems to indicate such problems
are not "new", aka, deps gen have 'support' for "generated" header files.
(except that it's pretty useless for -E type of usage since it suppress preproc
out):

From
http://gcc.gnu.org/onlinedocs/gcc/Preprocessor-Options.html#Preprocessor-Options
-MG
In conjunction with an option such as -M requesting dependency generation, -MG
assumes missing header files are generated files and adds them to the
dependency list without raising an error. The dependency filename is taken
directly from the #include directive without prepending any path. -MG also
suppresses preprocessed output, as a missing header file renders this useless.
This feature is used in automatic updating of makefiles.