Hi, Dodji, Thanks for helping update the patch. The new patch passed all regression test and can fix the problem in my huge source file. I added ChangeLog entry to the patch. Could any libcpp maintainers help check if it is ok for trunk?
Thanks, Dehao libcpp/ChangeLog: 2013-06-04 Dehao Chen <de...@google.com> * files.c (_cpp_stack_include): Fix the highest_location when header file is guarded by #ifndef and is included twice. Index: libcpp/files.c =================================================================== --- libcpp/files.c (revision 199570) +++ libcpp/files.c (working copy) @@ -983,6 +983,7 @@ _cpp_stack_include (cpp_reader *pfile, const char { struct cpp_dir *dir; _cpp_file *file; + bool stacked; dir = search_path_head (pfile, fname, angle_brackets, type); if (!dir) @@ -993,19 +994,26 @@ _cpp_stack_include (cpp_reader *pfile, const char if (type == IT_DEFAULT && file == NULL) return false; - /* Compensate for the increment in linemap_add that occurs in - _cpp_stack_file. In the case of a normal #include, we're - currently at the start of the line *following* the #include. A - separate source_location for this location makes no sense (until - we do the LC_LEAVE), and complicates LAST_SOURCE_LINE_LOCATION. - This does not apply if we found a PCH file (in which case - linemap_add is not called) or we were included from the - command-line. */ + /* Compensate for the increment in linemap_add that occurs if + _cpp_stack_file actually stacks the file. In the case of a + normal #include, we're currently at the start of the line + *following* the #include. A separate source_location for this + location makes no sense (until we do the LC_LEAVE), and + complicates LAST_SOURCE_LINE_LOCATION. This does not apply if we + found a PCH file (in which case linemap_add is not called) or we + were included from the command-line. */ if (file->pchname == NULL && file->err_no == 0 && type != IT_CMDLINE && type != IT_DEFAULT) pfile->line_table->highest_location--; - return _cpp_stack_file (pfile, file, type == IT_IMPORT); + stacked = _cpp_stack_file (pfile, file, type == IT_IMPORT); + + if (!stacked) + /* _cpp_stack_file didn't stack the file, so let's rollback the + compensation dance we performed above. */ + pfile->line_table->highest_location++; + + return stacked; } /* Could not open FILE. The complication is dependency output. */