Fix mcontext_t sigcontext namespace (bug 21457).

This patch completes the ucontext.h namespace fixes by fixing issues
related to the use of struct sigcontext as mcontext_t, and inclusion
of <bits/sigcontext.h> even when struct sigcontext is not so used.

Inclusion of <bits/sigcontext.h> by <sys/ucontext.h> is removed; the
way to get the sigcontext structure is by including <signal.h> (in a
context where __USE_MISC is defined); the sysdeps/generic version of
sys/ucontext.h keeps the inclusion by necessity, with a comment about
how this is not namespace-clean, but the only configuration that used
it, MicroBlaze, gets its own version of the header in this patch.
Where mcontext_t was typedefed to struct sigcontext, the contents of
struct sigcontext are inserted (with appropriate namespace handling to
prefix fields with __ when __USE_MISC is not defined); review should
check that this has been done correctly in each case, whether the
definition of struct sigcontext comes from glibc headers or from the
Linux kernel.  This changes C++ name mangling on affected
architectures (which do not include x86_64/x86).

Tested for x86_64, and with build-many-glibcs.py.

2017-08-14  Joseph Myers  <joseph@codesourcery.com>

	[BZ #21457]
	* sysdeps/arm/sys/ucontext.h: Do not include <bits/sigcontext.h>.
	* sysdeps/generic/sys/ucontext.h: Add comment about use of struct
	sigcontext and namespace requirements.
	* sysdeps/i386/sys/ucontext.h: Do not include <bits/sigcontext.h>.
	* sysdeps/m68k/sys/ucontext.h: Likewise.
	* sysdeps/mips/sys/ucontext.h: Likewise.  Include <bits/types.h>.
	* sysdeps/unix/sysv/linux/aarch64/sys/ucontext.h: Do not include
	<bits/sigcontext.h>.
	(__ctx): Define earlier.
	(mcontext_t): Define structure contents rather than using struct
	sigcontext.
	* sysdeps/unix/sysv/linux/aarch64/ucontext_i.sym (oEXTENSION): Use
	__glibc_reserved1 instead of __reserved.
	* sysdeps/unix/sysv/linux/alpha/sys/ucontext.h: Do not include
	<bits/sigcontext.h>.
	(__ctx): Define earlier.
	(mcontext_t): Define structure contents rather than using struct
	sigcontext.
	* sysdeps/unix/sysv/linux/alpha/ucontext-offsets.sym: Use
	mcontext_t instead of struct sigcontext.
	* sysdeps/unix/sysv/linux/arm/sys/ucontext.h: Do not include
	<bits/sigcontext.h>.
	(__ctx): Define earlier.
	(mcontext_t): Define structure contents rather than using struct
	sigcontext.
	* sysdeps/unix/sysv/linux/hppa/sys/ucontext.h: Do not include
	<bits/sigcontext.h>.
	(__ctx): Define earlier.
	(mcontext_t): Define structure contents rather than using struct
	sigcontext.
	* sysdeps/unix/sysv/linux/ia64/makecontext.c (__makecontext): Use
	mcontext_t instead of struct sigcontext.
	* sysdeps/unix/sysv/linux/ia64/sigcontext-offsets.sym: Use
	mcontext_t instead of struct sigcontext.
	* sysdeps/unix/sysv/linux/ia64/sys/ucontext.h: Do not include
	<bits/sigcontext.h>.
	(__ctx): New macro.
	(struct __ia64_fpreg_mcontext): New type.
	(mcontext_t): Define structure contents rather than using struct
	sigcontext.
	(_SC_GR0_OFFSET): Use mcontext_t instead of struct sigcontext.
	(uc_sigmask): Define using __ctx.
	(uc_stack): Likewise.
	* sysdeps/unix/sysv/linux/ia64/sys/procfs.h: Include
	<bits/sigcontext.h>.
	* sysdeps/unix/sysv/linux/ia64/sys/ptrace.h: Likewise.
	* sysdeps/unix/sysv/linux/m68k/sys/ucontext.h: Do not include
	<bits/sigcontext.h>.
	* sysdeps/unix/sysv/linux/microblaze/sys/ucontext.h: New file.
	* sysdeps/unix/sysv/linux/mips/sys/ucontext.h: Do not include
	<bits/sigcontext.h>.
	* sysdeps/unix/sysv/linux/nios2/sys/ucontext.h: Do not include
	<bits/sigcontext.h>.
	* sysdeps/unix/sysv/linux/powerpc/sys/ucontext.h: Do not include
	<bits/sigcontext.h>.
	* sysdeps/unix/sysv/linux/s390/sys/ucontext.h: Do not include
	<bits/sigcontext.h>.
	* sysdeps/unix/sysv/linux/sh/sys/ucontext.h: Do not include
	<bits/sigcontext.h>.
	* sysdeps/unix/sysv/linux/sparc/sys/ucontext.h: Do not include
	<bits/sigcontext.h>.
	* sysdeps/unix/sysv/linux/tile/sys/ucontext.h: Do not include
	<bits/sigcontext.h>.
	(__ctx): Define earlier.
	(mcontext_t): Define structure contents rather than using struct
	sigcontext.
	* sysdeps/unix/sysv/linux/x86/sys/ucontext.h: Do not include
	<bits/sigcontext.h>.  Include <bits/types.h>.
	* conform/Makefile (test-xfail-XPG42/signal.h/conform): Remove.
	(test-xfail-XPG42/sys/wait.h/conform): Likewise.
	(test-xfail-XPG42/ucontext.h/conform): Likewise.
	(test-xfail-UNIX98/signal.h/conform): Likewise.
	(test-xfail-UNIX98/sys/wait.h/conform): Likewise.
	(test-xfail-UNIX98/ucontext.h/conform): Likewise.
	(test-xfail-XOPEN2K/signal.h/conform): Likewise.
	(test-xfail-XOPEN2K/sys/wait.h/conform): Likewise.
	(test-xfail-XOPEN2K/ucontext.h/conform): Likewise.
	(test-xfail-POSIX2008/signal.h/conform): Likewise.
	(test-xfail-POSIX2008/sys/wait.h/conform): Likewise.
	(test-xfail-XOPEN2K8/signal.h/conform): Likewise.
	(test-xfail-XOPEN2K8/sys/wait.h/conform): Likewise.

5 files changed, 61 insertions, 20 deletions

diff --git a/sysdeps/unix/sysv/linux/ia64/makecontext.c b/sysdeps/unix/sysv/linux/ia64/makecontext.c
index 299f9a85ae..cb98e7cb13 100644
--- a/sysdeps/unix/sysv/linux/ia64/makecontext.c
+++ b/sysdeps/unix/sysv/linux/ia64/makecontext.c
@@ -40,7 +40,7 @@ do {						\
 void
 __makecontext (ucontext_t *ucp, void (*func) (void), int argc, ...)
 {
-  struct sigcontext *sc = &ucp->uc_mcontext;
+  mcontext_t *sc = &ucp->uc_mcontext;
   extern void __start_context (ucontext_t *link, long gp, ...);
   unsigned long stack_start, stack_end;
   va_list ap;
diff --git a/sysdeps/unix/sysv/linux/ia64/sigcontext-offsets.sym b/sysdeps/unix/sysv/linux/ia64/sigcontext-offsets.sym
index 943e68a667..ac3e3c8dea 100644
--- a/sysdeps/unix/sysv/linux/ia64/sigcontext-offsets.sym
+++ b/sysdeps/unix/sysv/linux/ia64/sigcontext-offsets.sym
@@ -2,15 +2,15 @@
 #include <sys/ucontext.h>
 
 --
-SC_NAT		offsetof (struct sigcontext, sc_nat)
-SC_BSP		offsetof (struct sigcontext, sc_ar_bsp)
-SC_RNAT		offsetof (struct sigcontext, sc_ar_rnat)
-SC_UNAT		offsetof (struct sigcontext, sc_ar_unat)
-SC_FPSR		offsetof (struct sigcontext, sc_ar_fpsr)
-SC_PFS		offsetof (struct sigcontext, sc_ar_pfs)
-SC_LC		offsetof (struct sigcontext, sc_ar_lc)
-SC_PR		offsetof (struct sigcontext, sc_pr)
-SC_BR		offsetof (struct sigcontext, sc_br)
-SC_GR		offsetof (struct sigcontext, sc_gr)
-SC_FR		offsetof (struct sigcontext, sc_fr)
-SC_MASK		offsetof (struct sigcontext, sc_mask)
+SC_NAT		offsetof (mcontext_t, sc_nat)
+SC_BSP		offsetof (mcontext_t, sc_ar_bsp)
+SC_RNAT		offsetof (mcontext_t, sc_ar_rnat)
+SC_UNAT		offsetof (mcontext_t, sc_ar_unat)
+SC_FPSR		offsetof (mcontext_t, sc_ar_fpsr)
+SC_PFS		offsetof (mcontext_t, sc_ar_pfs)
+SC_LC		offsetof (mcontext_t, sc_ar_lc)
+SC_PR		offsetof (mcontext_t, sc_pr)
+SC_BR		offsetof (mcontext_t, sc_br)
+SC_GR		offsetof (mcontext_t, sc_gr)
+SC_FR		offsetof (mcontext_t, sc_fr)
+SC_MASK		offsetof (mcontext_t, sc_mask)
diff --git a/sysdeps/unix/sysv/linux/ia64/sys/procfs.h b/sysdeps/unix/sysv/linux/ia64/sys/procfs.h
index afe54fbd53..4847f2d59b 100644
--- a/sysdeps/unix/sysv/linux/ia64/sys/procfs.h
+++ b/sysdeps/unix/sysv/linux/ia64/sys/procfs.h
@@ -27,6 +27,7 @@
 #include <sys/time.h>
 #include <sys/types.h>
 #include <sys/ucontext.h>
+#include <bits/sigcontext.h>
 #include <sys/user.h>
 
 __BEGIN_DECLS
diff --git a/sysdeps/unix/sysv/linux/ia64/sys/ptrace.h b/sysdeps/unix/sysv/linux/ia64/sys/ptrace.h
index 681dc8913a..9de2f9431b 100644
--- a/sysdeps/unix/sysv/linux/ia64/sys/ptrace.h
+++ b/sysdeps/unix/sysv/linux/ia64/sys/ptrace.h
@@ -21,6 +21,7 @@
 
 #include <features.h>
 #include <sys/ucontext.h>
+#include <bits/sigcontext.h>
 #include <bits/types.h>
 
 __BEGIN_DECLS
diff --git a/sysdeps/unix/sysv/linux/ia64/sys/ucontext.h b/sysdeps/unix/sysv/linux/ia64/sys/ucontext.h
index 9cd686c40c..8929e093a0 100644
--- a/sysdeps/unix/sysv/linux/ia64/sys/ucontext.h
+++ b/sysdeps/unix/sysv/linux/ia64/sys/ucontext.h
@@ -21,24 +21,63 @@
 #include <features.h>
 
 #include <bits/types/sigset_t.h>
-#include <bits/sigcontext.h>
 #include <bits/types/stack_t.h>
 
 
+#ifdef __USE_MISC
+# define __ctx(fld) fld
+#else
+# define __ctx(fld) __ ## fld
+#endif
+
 /*
  * These are here mostly for backwards compatibility with older Unices.
- * IA-64 Linux does not distinguish between "struct sigcontext" and
+ * IA-64 Linux does not distinguish between "mcontext_t" and
  * "ucontext_t" as all the necessary info is inside the former.
  */
 
-typedef struct sigcontext mcontext_t;
+struct __ia64_fpreg_mcontext
+  {
+    union
+      {
+	unsigned long __ctx(bits)[2];
+      } __ctx(u);
+  } __attribute__ ((__aligned__ (16)));
+
+typedef struct
+  {
+    unsigned long int __ctx(sc_flags);
+    unsigned long int __ctx(sc_nat);
+    stack_t __ctx(sc_stack);
+    unsigned long int __ctx(sc_ip);
+    unsigned long int __ctx(sc_cfm);
+    unsigned long int __ctx(sc_um);
+    unsigned long int __ctx(sc_ar_rsc);
+    unsigned long int __ctx(sc_ar_bsp);
+    unsigned long int __ctx(sc_ar_rnat);
+    unsigned long int __ctx(sc_ar_ccv);
+    unsigned long int __ctx(sc_ar_unat);
+    unsigned long int __ctx(sc_ar_fpsr);
+    unsigned long int __ctx(sc_ar_pfs);
+    unsigned long int __ctx(sc_ar_lc);
+    unsigned long int __ctx(sc_pr);
+    unsigned long int __ctx(sc_br)[8];
+    unsigned long int __ctx(sc_gr)[32];
+    struct __ia64_fpreg_mcontext __ctx(sc_fr)[128];
+    unsigned long int __ctx(sc_rbs_base);
+    unsigned long int __ctx(sc_loadrs);
+    unsigned long int __ctx(sc_ar25);
+    unsigned long int __ctx(sc_ar26);
+    unsigned long int __ctx(sc_rsvd)[12];
+    unsigned long int __ctx(sc_mask);
+  } mcontext_t;
 
 #if __GNUC_PREREQ (3, 5)
 # define _SC_GR0_OFFSET	\
-	__builtin_offsetof (struct sigcontext, sc_gr[0])
+	__builtin_offsetof (mcontext_t, __ctx(sc_gr)[0])
 #elif defined __GNUC__
 # define _SC_GR0_OFFSET	\
-	(((char *) &((struct sigcontext *) 0)->sc_gr[0]) - (char *) 0)
+	(((char *) &((mcontext_t *) 0)->__ctx(sc_gr)[0]) - (char *) 0)
 #else
 # define _SC_GR0_OFFSET	0xc8	/* pray that this is correct... */
 #endif
@@ -60,8 +99,8 @@ typedef struct ucontext_t
 ucontext_t;
 
 #define uc_mcontext	_u._mc
-#define uc_sigmask	_u._mc.sc_mask
-#define uc_stack	_u._mc.sc_stack
+#define uc_sigmask	_u._mc.__ctx(sc_mask)
+#define uc_stack	_u._mc.__ctx(sc_stack)
 #define uc_link		_u._uc._link
 
 #endif /* sys/ucontext.h */