conformtest: Support xfail markers on individual assertions.

Various conformtest tests fail because of known issues, filed in
Bugzilla, that are hard to fix (requiring new features, kernel
cooperation or involving changing types in ways that may involve care
around padding when interfacing to the kernel).  Such an issue has the
effect of making the whole test for the (standard, header) pair fail,
so hiding any other issues with that header for that standard
(possibly regressions or architecture-specific issues).

This patch adds a mechanism for individual conformtest test
expectations to start with xfail-, meaning that a failure of that
particular assertion does not cause the whole test to fail at the
makefile level and so failure at the makefile level can be used to
detect other issues that are likely to be easier to fix.  This is
similar to the whitelisted symbols in the linknamespace tests, or the
marking of particular libm tests as allowing spurious or missing
exceptions, for example.  The bugs filed in Bugzilla should still be
fixed, and the xfail- markers removed at that point, but xfail-
renders the tests more useful until that happens.

Note that there is no way to add such a marker for the assertion that
a header uses only symbols in the namespace of symbols it's meant to
use.  I don't think there's any need for a way to xfail those
namespace tests other than xfailing the whole (standard, header) pair
at the makefile level, since they are generally straightforward to fix
(add appropriate conditionals on the problem definitions).

The xfails in this patch do not necessarily cover all cases of
hard-to-fix header bugs filed in Bugzilla that currently show up in
conformtest failures; there may be more yet to add for existing open
bugs.

Tested for x86_64 and x86.

	* conform/conformtest.pl ($xerrors): New variable.
	(note_error): New function.
	(compiletest): New argument $xfail.  Use not_error.
	(runtest): Likewise.
	(top level): Handle xfail- lines.  Update calls to compiletest and
	runtest.  Handle xfail- and optional- in headers listed with
	allow-header.
	* conform/data/fcntl.h-data (O_TTY_INIT): Use xfail-.
	(O_EXEC): Likewise.
	(O_SEARCH): Likewise.
	* conform/data/stropts.h-data (ioctl): Likewise.
	* conform/data/sys/ipc.h-data (ipc_perm.mode): Likewise.
	* conform/data/sys/sem.h-data (semid_ds.sem_nsems): Likewise.
	* conform/data/sys/socket.h-data (msghdr.msg_iovlen): Likewise.
	(msghdr.msg_controllen): Likewise.
	(cmsghdr.cmsg_len): Likewise.
	* conform/data/utmpx.h-data (utmpx.ut_tv): Likewise.
	* conform/Makefile (test-xfail-XPG3/sys/ipc.h/conform): Remove
	variable.
	(test-xfail-XPG3/sys/sem.h/conform): Likewise.
	(test-xfail-XPG4/stropts.h/conform): Likewise.
	(test-xfail-XPG4/sys/ipc.h/conform): Likewise.
	(test-xfail-XPG4/sys/sem.h/conform): Likewise.
	(test-xfail-XPG4/sys/socket.h/conform): Likewise.
	(test-xfail-UNIX98/stropts.h/conform): Likewise.
	(test-xfail-UNIX98/sys/ipc.h/conform): Likewise.
	(test-xfail-UNIX98/sys/sem.h/conform): Likewise.
	(test-xfail-UNIX98/sys/socket.h/conform): Likewise.
	(test-xfail-XOPEN2K/stropts.h/conform): Likewise.
	(test-xfail-XOPEN2K/sys/ipc.h/conform): Likewise.
	(test-xfail-XOPEN2K/sys/sem.h/conform): Likewise.
	(test-xfail-XOPEN2K/sys/socket.h/conform): Likewise.
	(test-xfail-XOPEN2K/utmpx.h/conform): Likewise.
	(test-xfail-POSIX2008/fcntl.h/conform): Likewise.
	(test-xfail-POSIX2008/stropts.h/conform): Likewise.
	(test-xfail-XOPEN2K8/fcntl.h/conform): Likewise.
	(test-xfail-XOPEN2K8/stropts.h/conform): Likewise.
	(test-xfail-XOPEN2K8/sys/ipc.h/conform): Likewise.
	(test-xfail-XOPEN2K8/sys/sem.h/conform): Likewise.
	(test-xfail-XOPEN2K8/sys/socket.h/conform): Likewise.

6 files changed, 19 insertions, 10 deletions

diff --git a/conform/data/fcntl.h-data b/conform/data/fcntl.h-data
index efe134e448..1971d4a742 100644
--- a/conform/data/fcntl.h-data
+++ b/conform/data/fcntl.h-data
@@ -113,10 +113,11 @@ function int posix_fallocate (int, off_t, off_t)
 #endif
 
 #if defined XOPEN2K8 || defined POSIX2008
-constant O_TTY_INIT
+// Bug 18228: O_TTY_INIT, O_EXEC, O_SEARCH missing.
+xfail-constant O_TTY_INIT
 constant O_CLOEXEC
-constant O_EXEC
-constant O_SEARCH
+xfail-constant O_EXEC
+xfail-constant O_SEARCH
 constant O_DIRECTORY
 constant O_NOFOLLOW
 constant F_DUPFD_CLOEXEC
diff --git a/conform/data/stropts.h-data b/conform/data/stropts.h-data
index 6849fecc87..e43dac8c9e 100644
--- a/conform/data/stropts.h-data
+++ b/conform/data/stropts.h-data
@@ -115,7 +115,8 @@ macro MOREDATA
 function int isastream (int)
 function int getmsg (int, struct strbuf*, struct strbuf*, int*)
 function int getpmsg (int, struct strbuf*, struct strbuf*, int*, int*)
-function int ioctl (int, int, ...)
+// Bug 14362: wrong type for ioctl.
+xfail-function int ioctl (int, int, ...)
 function int putmsg (int, const struct strbuf*, const struct strbuf*, int)
 function int putpmsg (int, const struct strbuf*, const struct strbuf*, int, int)
 function int fattach (int, const char*)
diff --git a/conform/data/sys/ipc.h-data b/conform/data/sys/ipc.h-data
index 8f06d2ba0a..70dc3f6fe6 100644
--- a/conform/data/sys/ipc.h-data
+++ b/conform/data/sys/ipc.h-data
@@ -5,7 +5,8 @@ element {struct ipc_perm} uid_t uid
 element {struct ipc_perm} gid_t gid
 element {struct ipc_perm} uid_t cuid
 element {struct ipc_perm} gid_t cgid
-element {struct ipc_perm} mode_t mode
+// Bug 18231: wrong type for mode member.
+xfail-element {struct ipc_perm} mode_t mode
 
 type uid_t
 type gid_t
diff --git a/conform/data/sys/sem.h-data b/conform/data/sys/sem.h-data
index 61eecf2951..a36ab1bd91 100644
--- a/conform/data/sys/sem.h-data
+++ b/conform/data/sys/sem.h-data
@@ -12,7 +12,8 @@ constant SETALL
 type {struct semid_ds}
 
 element {struct semid_ds} {struct ipc_perm} sem_perm
-element {struct semid_ds} {unsigned short int} sem_nsems
+// Bug 18232: wrong type for sem_nsems member.
+xfail-element {struct semid_ds} {unsigned short int} sem_nsems
 element {struct semid_ds} time_t sem_otime
 element {struct semid_ds} time_t sem_ctime
 
diff --git a/conform/data/sys/socket.h-data b/conform/data/sys/socket.h-data
index 3a6cf7c673..442d4d288a 100644
--- a/conform/data/sys/socket.h-data
+++ b/conform/data/sys/socket.h-data
@@ -22,9 +22,10 @@ type {struct msghdr}
 element {struct msghdr} {void*} msg_name
 element {struct msghdr} socklen_t msg_namelen
 element {struct msghdr} {struct iovec*} msg_iov
-element {struct msghdr} int msg_iovlen
+// Bug 16919: wrong type for msg_iovlen and msg_controllen members.
+xfail-element {struct msghdr} int msg_iovlen
 element {struct msghdr} {void*} msg_control
-element {struct msghdr} socklen_t msg_controllen
+xfail-element {struct msghdr} socklen_t msg_controllen
 element {struct msghdr} int msg_flags
 
 type {struct iovec}
@@ -34,7 +35,8 @@ element {struct iovec} size_t iov_len
 
 type {struct cmsghdr}
 
-element {struct cmsghdr} socklen_t cmsg_len
+// Bug 16919: wrong type for cmsg_len member.
+xfail-element {struct cmsghdr} socklen_t cmsg_len
 element {struct cmsghdr} int cmsg_level
 element {struct cmsghdr} int cmsg_type
 
diff --git a/conform/data/utmpx.h-data b/conform/data/utmpx.h-data
index b8a0062321..80641ff8f0 100644
--- a/conform/data/utmpx.h-data
+++ b/conform/data/utmpx.h-data
@@ -6,7 +6,10 @@ element {struct utmpx} char ut_id []
 element {struct utmpx} char ut_line []
 element {struct utmpx} pid_t ut_pid
 element {struct utmpx} {short int} ut_type
-element {struct utmpx} {struct timeval} ut_tv
+// Layout chosen to be compatible on 32-bit and 64-bit bi-arch
+// systems, which is incompatible with the standard type (see bug
+// 18235).
+xfail-element {struct utmpx} {struct timeval} ut_tv
 
 type pid_t