From mboxrd@z Thu Jan 1 00:00:00 1970 From: "John Hughes" To: nobody@gcc.gnu.org Cc: gcc-prs@gcc.gnu.org Subject: RE: bootstrap/3163 Date: Thu, 14 Jun 2001 00:36:00 -0000 Message-id: <20010614073601.10643.qmail@sourceware.cygnus.com> X-SW-Source: 2001-06/msg00620.html List-Id: The following reply was made to PR bootstrap/3163; it has been noted by GNATS. From: "John Hughes" To: "Robert Lipe" , , , , Cc: Subject: RE: bootstrap/3163 Date: Thu, 14 Jun 2001 09:28:32 +0200 >> http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view&pr=3163&database=gcc >> No OS has yet been observed to be so perverse as to leave unmapped >> space between consecutive calls to mmap. */ >> >> Well, UnixWare 7.1.1 is that perverse system. It seems to leave >> one page between each mapping. > This is actually documented behaviour. From the mmap man page: > > References to pages in a mapped region which are beyond the > page containing the end of a file will result in the delivery of a > SIGBUS signal. No, that paragraph says that if I mmap 10 pages from a 5 page file access to the 5 pages beyond eof get a SIGBUS (note: not SIGSEGV). It says nothing about memory OUTSIDE the mmaped region.