Installed header hygiene (BZ#20366): Test of installed headers.

This adds a test to ensure that the problems fixed in the last several
patches do not recur.  Each directory checks the headers that it
installs for two properties: first, each header must be compilable in
isolation, as both C and C++, under a representative combination of
language and library conformance levels; second, there is a blacklist
of identifiers that may not appear in any installed header, currently
consisting of the legacy BSD typedefs.  (There is an exemption for the
headers that define those typedefs, and for the RPC headers.  It may be
necessary to make this more sophisticated if we add more stuff to the
blacklist in the future.)

In order for this test to work correctly, every wrapper header
that actually defines something must guard those definitions with
 #ifndef _ISOMAC.  This is the existing mechanism used by the conform/
tests to tell wrapper headers not to define anything that the public
header wouldn't, and not to use anything from libc-symbols.h.  conform/
only cares for headers that we need to check for standards conformance,
whereas this test applies to *every* header.  (Headers in include/ that
are either installed directly, or are internal-use-only and do *not*
correspond to any installed header, are not affected.)

	* scripts/check-installed-headers.sh: New script.
	* Rules: In each directory that defines header files to be installed,
	run check-installed-headers.sh on them as a special test.
	* Makefile: Likewise for the headers installed at top level.

	* include/aliases.h, include/alloca.h, include/argz.h
	* include/arpa/nameser.h, include/arpa/nameser_compat.h
	* include/elf.h, include/envz.h, include/err.h
	* include/execinfo.h, include/fpu_control.h, include/getopt.h
	* include/gshadow.h, include/ifaddrs.h, include/libintl.h
	* include/link.h, include/malloc.h, include/mcheck.h
	* include/mntent.h, include/netinet/ether.h
	* include/nss.h, include/obstack.h, include/printf.h
	* include/pty.h, include/resolv.h, include/rpc/auth.h
	* include/rpc/auth_des.h, include/rpc/auth_unix.h
	* include/rpc/clnt.h, include/rpc/des_crypt.h
	* include/rpc/key_prot.h, include/rpc/netdb.h
	* include/rpc/pmap_clnt.h, include/rpc/pmap_prot.h
	* include/rpc/pmap_rmt.h, include/rpc/rpc.h
	* include/rpc/rpc_msg.h, include/rpc/svc.h
	* include/rpc/svc_auth.h, include/rpc/xdr.h
	* include/rpcsvc/nis_callback.h, include/rpcsvc/nislib.h
	* include/rpcsvc/yp.h, include/rpcsvc/ypclnt.h
	* include/rpcsvc/ypupd.h, include/shadow.h
	* include/stdio_ext.h, include/sys/epoll.h
	* include/sys/file.h, include/sys/gmon.h, include/sys/ioctl.h
	* include/sys/prctl.h, include/sys/profil.h
	* include/sys/statfs.h, include/sys/sysctl.h
	* include/sys/sysinfo.h, include/ttyent.h, include/utmp.h
	* sysdeps/arm/nacl/include/bits/setjmp.h
	* sysdeps/mips/include/sys/asm.h
	* sysdeps/unix/sysv/linux/include/sys/sysinfo.h
	* sysdeps/unix/sysv/linux/include/sys/timex.h
	* sysdeps/x86/fpu/include/bits/fenv.h:
	Add #ifndef _ISOMAC guard around internal declarations.
	Add multiple-inclusion guard if not already present.

5 files changed, 19 insertions, 2 deletions

diff --git a/sysdeps/arm/nacl/include/bits/setjmp.h b/sysdeps/arm/nacl/include/bits/setjmp.h
index 6b6a235..e1fe505 100644
--- a/sysdeps/arm/nacl/include/bits/setjmp.h
+++ b/sysdeps/arm/nacl/include/bits/setjmp.h
@@ -24,6 +24,8 @@
 # include <sysdeps/arm/bits/setjmp.h>
 #endif
 
+# ifndef _ISOMAC
+
 /* Register list for a ldm/stm instruction to load/store
    the general registers from a __jmp_buf.
 
@@ -35,4 +37,5 @@
 /* Index of __jmp_buf where the sp register resides.  */
 #define __JMP_BUF_SP		0
 
+# endif /* _ISOMAC */
 #endif  /* include/bits/setjmp.h */
diff --git a/sysdeps/mips/include/sys/asm.h b/sysdeps/mips/include/sys/asm.h
index 7e288df..67acf74 100644
--- a/sysdeps/mips/include/sys/asm.h
+++ b/sysdeps/mips/include/sys/asm.h
@@ -16,8 +16,9 @@
    <http://www.gnu.org/licenses/>.  */
 
 #ifndef _SYS_ASM_H
+#include_next <sys/asm.h>
 
-# include_next <sys/asm.h>
+# ifndef _ISOMAC
 
 # undef __mips_cfi_startproc
 # define __mips_cfi_startproc cfi_startproc
@@ -50,4 +51,5 @@
 	cfi_restore (gp)
 # endif
 
-#endif
+# endif /* _ISOMAC */
+#endif /* sys/asm.h */
diff --git a/sysdeps/unix/sysv/linux/include/sys/sysinfo.h b/sysdeps/unix/sysv/linux/include/sys/sysinfo.h
index 50077fb..b76f7e0 100644
--- a/sysdeps/unix/sysv/linux/include/sys/sysinfo.h
+++ b/sysdeps/unix/sysv/linux/include/sys/sysinfo.h
@@ -21,6 +21,9 @@
 
 #include_next <sys/sysinfo.h>
 
+# ifndef _ISOMAC
+
 extern __typeof (sysinfo) __sysinfo __THROW;
 
+# endif /* _ISOMAC */
 #endif /* sys/sysinfo.h */
diff --git a/sysdeps/unix/sysv/linux/include/sys/timex.h b/sysdeps/unix/sysv/linux/include/sys/timex.h
index ace90ee..4b4ff88 100644
--- a/sysdeps/unix/sysv/linux/include/sys/timex.h
+++ b/sysdeps/unix/sysv/linux/include/sys/timex.h
@@ -21,6 +21,9 @@
 
 #include_next <sys/timex.h>
 
+# ifndef _ISOMAC
+
 libc_hidden_proto (__adjtimex)
 
+# endif /* _ISOMAC */
 #endif /* sys/timex.h */
diff --git a/sysdeps/x86/fpu/include/bits/fenv.h b/sysdeps/x86/fpu/include/bits/fenv.h
index 6e8b733..a410ed0 100644
--- a/sysdeps/x86/fpu/include/bits/fenv.h
+++ b/sysdeps/x86/fpu/include/bits/fenv.h
@@ -16,8 +16,11 @@
    License along with the GNU C Library; if not, see
    <http://www.gnu.org/licenses/>.  */
 
+#ifndef _BITS_FENV_H
 #include_next <bits/fenv.h>
 
+# ifndef _ISOMAC
+
 /* Ensure __feraiseexcept calls in glibc are optimized the same as
    feraiseexcept calls.  */
 
@@ -40,3 +43,6 @@ __NTH (__feraiseexcept (int __excepts))
 
 __END_DECLS
 #endif
+
+# endif /* _ISOMAC */
+#endif /* bits/fenv.h */