diff options
Diffstat (limited to 'gcc/cppfiles.c')
| -rw-r--r-- | gcc/cppfiles.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/gcc/cppfiles.c b/gcc/cppfiles.c index f0d85d9..65bcf62 100644 --- a/gcc/cppfiles.c +++ b/gcc/cppfiles.c @@ -382,6 +382,11 @@ read_include_file (pfile, inc) if (pagesize == -1) pagesize = getpagesize (); + /* Use mmap if the file is big enough to be worth it (controlled + by MMAP_THRESHOLD) and if we can safely count on there being + at least one readable NUL byte after the end of the file's + contents. This is true for all tested operating systems when + the file size is not an exact multiple of the page size. */ if (size / pagesize >= MMAP_THRESHOLD && (size % pagesize) != 0) { |