While working on PR 55399 (pch broken on mips-mti-linux-gnu) I traced
through the execution of test gcc.dg/pch/common-1.c and in comparing r192714
and r192715 I found that in the earlier version the compiler gets to
pch_open_file (with common-1.h) and does this check:
if (pfile->all_files
&& pfile->all_files->next_file) {
it finds that pfile->all_files->next_file is NULL and continues on in the
routine.
In the new version there is:
if (pfile->all_files
&& pfile->all_files->next_file
&& !pfile->all_files->next_file->implicit_preinclude) {
and here it finds that pfile->all_files->next_file is true but
pfile->all_files->next_file->implicit_preinclude is false so it exits
the routine and this is why the code compiler doesn't find the
preprocessed header file.
Looking at pfile I see that pfile->all_files is pointing at stdc-predef.h
where implicit_preinclude is true but pfile->all_files->next_file is pointing
at common-1.c where implicit_preinclude is false.
My best guess as to why this is happening for me and not other people is that
the order of common-1.c and stdc-predef.h in this linked list is dependent on
how things are put into pfile->file_hash and for some reason stdc-predef.h
shows up before common-1.c for me but not for other people, where they get
common-1.c and then stdc-predef.h.
This patch checks for implicit_preinclude on both pfile->all_files and
pfile->all_files->next_file and it fixes the problem for me. I tested
it on mips-mti-linux-gnu and had no regressions.
OK to checkin?
Steve Ellcey
sell...@mips.com
2012-11-21 Steve Ellcey <sell...@mips.com>
PR pch/55399
* files.c (pch_open_file): Fix check for implicit_preinclude.
diff --git a/libcpp/files.c b/libcpp/files.c
index a8288dc..9f84d8c 100644
--- a/libcpp/files.c
+++ b/libcpp/files.c
@@ -295,7 +295,8 @@ pch_open_file (cpp_reader *pfile, _cpp_file *file, bool
*invalid_pch)
file or the command-line it is not a valid use of PCH. */
if (pfile->all_files
&& pfile->all_files->next_file
- && !pfile->all_files->next_file->implicit_preinclude)
+ && !(pfile->all_files->implicit_preinclude
+ || pfile->all_files->next_file->implicit_preinclude))
return false;
flen = strlen (path);
