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.

29 files changed, 369 insertions, 96 deletions

diff --git a/ChangeLog b/ChangeLog
index 1d8bcde330..988c4024d7 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,88 @@
+2017-08-30  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.
+
 2017-08-30  Florian Weimer  <fweimer@redhat.com>
 
 	* malloc/dynarray_emplace_enlarge.c
diff --git a/NEWS b/NEWS
index 625bcc60b6..dce514dac7 100644
--- a/NEWS
+++ b/NEWS
@@ -33,6 +33,10 @@ Deprecated and removed features, and other changes affecting compatibility:
   exception, or the macros X_TLOSS, DOMAIN, SING, OVERFLOW, UNDERFLOW,
   TLOSS, PLOSS and HUGE.
 
+* The mcontext_t type is no longer the same as struct sigcontext.  On
+  platforms where it was previously the same, this changes the C++ name
+  mangling for interfaces involving this type.
+
 Changes to build and runtime requirements:
 
   [Add changes to build and runtime requirements here]
diff --git a/conform/Makefile b/conform/Makefile
index 9ec41c7244..3883a4bcf2 100644
--- a/conform/Makefile
+++ b/conform/Makefile
@@ -160,21 +160,6 @@ test-xfail-UNIX98/ndbm.h/conform = yes
 test-xfail-XOPEN2K/ndbm.h/conform = yes
 test-xfail-XOPEN2K8/ndbm.h/conform = yes
 
-# Unsorted expected failures.
-test-xfail-XPG42/signal.h/conform = yes
-test-xfail-XPG42/sys/wait.h/conform = yes
-test-xfail-XPG42/ucontext.h/conform = yes
-test-xfail-UNIX98/signal.h/conform = yes
-test-xfail-UNIX98/sys/wait.h/conform = yes
-test-xfail-UNIX98/ucontext.h/conform = yes
-test-xfail-XOPEN2K/signal.h/conform = yes
-test-xfail-XOPEN2K/sys/wait.h/conform = yes
-test-xfail-XOPEN2K/ucontext.h/conform = yes
-test-xfail-POSIX2008/signal.h/conform = yes
-test-xfail-POSIX2008/sys/wait.h/conform = yes
-test-xfail-XOPEN2K8/signal.h/conform = yes
-test-xfail-XOPEN2K8/sys/wait.h/conform = yes
-
 conformtest-cc-flags = -I../include $(+sysdep-includes) $(sysincludes) -I..
 # conformtest-xfail-conds may be set by a sysdeps Makefile fragment to
 # a list of conditions that are considered to be true when encountered
diff --git a/sysdeps/arm/sys/ucontext.h b/sysdeps/arm/sys/ucontext.h
index da749a96da..512d51fa7a 100644
--- a/sysdeps/arm/sys/ucontext.h
+++ b/sysdeps/arm/sys/ucontext.h
@@ -23,7 +23,6 @@
 #include <features.h>
 
 #include <bits/types/sigset_t.h>
-#include <bits/sigcontext.h>
 #include <bits/types/stack_t.h>
 
 
diff --git a/sysdeps/generic/sys/ucontext.h b/sysdeps/generic/sys/ucontext.h
index ec5ab943cc..d497297e2e 100644
--- a/sysdeps/generic/sys/ucontext.h
+++ b/sysdeps/generic/sys/ucontext.h
@@ -17,7 +17,9 @@
    <http://www.gnu.org/licenses/>.  */
 
 /* This file's definitions suffice for any platform where all
-   the machine-specific state is described in `struct sigcontext'.  */
+   the machine-specific state is described in `struct sigcontext', but
+   use of struct sigcontext does not conform to POSIX namespace
+   requirements.  */
 
 #ifndef _SYS_UCONTEXT_H
 #define _SYS_UCONTEXT_H	1
diff --git a/sysdeps/i386/sys/ucontext.h b/sysdeps/i386/sys/ucontext.h
index 27f5e48559..440075cb99 100644
--- a/sysdeps/i386/sys/ucontext.h
+++ b/sysdeps/i386/sys/ucontext.h
@@ -23,7 +23,6 @@
 #include <features.h>
 
 #include <bits/types/sigset_t.h>
-#include <bits/sigcontext.h>
 #include <bits/types/stack_t.h>
 
 
diff --git a/sysdeps/m68k/sys/ucontext.h b/sysdeps/m68k/sys/ucontext.h
index 9d2b2c6c2c..0dbdca6dca 100644
--- a/sysdeps/m68k/sys/ucontext.h
+++ b/sysdeps/m68k/sys/ucontext.h
@@ -23,7 +23,6 @@
 #include <features.h>
 
 #include <bits/types/sigset_t.h>
-#include <bits/sigcontext.h>
 #include <bits/types/stack_t.h>
 
 
diff --git a/sysdeps/mips/sys/ucontext.h b/sysdeps/mips/sys/ucontext.h
index 8248f5935d..d2a7ae3354 100644
--- a/sysdeps/mips/sys/ucontext.h
+++ b/sysdeps/mips/sys/ucontext.h
@@ -22,8 +22,8 @@
 
 #include <features.h>
 
+#include <bits/types.h>
 #include <bits/types/sigset_t.h>
-#include <bits/sigcontext.h>
 #include <bits/types/stack_t.h>
 
 #include <sgidefs.h>
diff --git a/sysdeps/unix/sysv/linux/aarch64/sys/ucontext.h b/sysdeps/unix/sysv/linux/aarch64/sys/ucontext.h
index 62ba382f0d..3de801133a 100644
--- a/sysdeps/unix/sysv/linux/aarch64/sys/ucontext.h
+++ b/sysdeps/unix/sysv/linux/aarch64/sys/ucontext.h
@@ -24,10 +24,15 @@
 #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
+
+#ifdef __USE_MISC
 # include <sys/procfs.h>
 
 
@@ -44,13 +49,15 @@ typedef elf_fpregset_t	fpregset_t;
    the core registers; coprocessor registers get saved elsewhere
    (e.g. in uc_regspace, or somewhere unspecified on the stack
    during non-RT signal handlers).  */
-typedef struct sigcontext mcontext_t;
-
-#ifdef __USE_MISC
-# define __ctx(fld) fld
-#else
-# define __ctx(fld) __ ## fld
-#endif
+typedef struct
+  {
+    unsigned long long int __ctx(fault_address);
+    unsigned long long int __ctx(regs)[31];
+    unsigned long long int __ctx(sp);
+    unsigned long long int __ctx(pc);
+    unsigned long long int __ctx(pstate);
+    unsigned char __glibc_reserved1[4096] __attribute__ ((__aligned__ (16)));
+  } mcontext_t;
 
 /* Userlevel context.  */
 typedef struct ucontext_t
diff --git a/sysdeps/unix/sysv/linux/aarch64/ucontext_i.sym b/sysdeps/unix/sysv/linux/aarch64/ucontext_i.sym
index ab3930c173..479bdda5c6 100644
--- a/sysdeps/unix/sysv/linux/aarch64/ucontext_i.sym
+++ b/sysdeps/unix/sysv/linux/aarch64/ucontext_i.sym
@@ -38,7 +38,7 @@ oX0				mcontext (regs)
 oSP				mcontext (sp)
 oPC				mcontext (pc)
 oPSTATE				mcontext (pstate)
-oEXTENSION                      mcontext (__reserved)
+oEXTENSION                      mcontext (__glibc_reserved1)
 
 #define fpsimd_context(member)  offsetof (struct fpsimd_context, member)
 
diff --git a/sysdeps/unix/sysv/linux/alpha/sys/ucontext.h b/sysdeps/unix/sysv/linux/alpha/sys/ucontext.h
index af20177556..a51d9b2d5e 100644
--- a/sysdeps/unix/sysv/linux/alpha/sys/ucontext.h
+++ b/sysdeps/unix/sysv/linux/alpha/sys/ucontext.h
@@ -21,10 +21,15 @@
 #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
+
 /* Type for general register.  */
 typedef long int greg_t;
 
@@ -51,13 +56,27 @@ typedef fpreg_t fpregset_t[__NFPREG];
 
 
 /* A machine context is exactly a sigcontext.  */
-typedef struct sigcontext mcontext_t;
-
-#ifdef __USE_MISC
-# define __ctx(fld) fld
-#else
-# define __ctx(fld) __ ## fld
-#endif
+typedef struct
+  {
+    long int __ctx(sc_onstack);
+    long int __ctx(sc_mask);
+    long int __ctx(sc_pc);
+    long int __ctx(sc_ps);
+    long int __ctx(sc_regs)[32];
+    long int __ctx(sc_ownedfp);
+    long int __ctx(sc_fpregs)[32];
+    unsigned long int __ctx(sc_fpcr);
+    unsigned long int __ctx(sc_fp_control);
+    unsigned long int __glibc_reserved1, __glibc_reserved2;
+    unsigned long int __ctx(sc_ssize);
+    char *__ctx(sc_sbase);
+    unsigned long int __ctx(sc_traparg_a0);
+    unsigned long int __ctx(sc_traparg_a1);
+    unsigned long int __ctx(sc_traparg_a2);
+    unsigned long int __ctx(sc_fp_trap_pc);
+    unsigned long int __ctx(sc_fp_trigger_sum);
+    unsigned long int __ctx(sc_fp_trigger_inst);
+  } mcontext_t;
 
 /* Userlevel context.  */
 typedef struct ucontext_t
diff --git a/sysdeps/unix/sysv/linux/alpha/ucontext-offsets.sym b/sysdeps/unix/sysv/linux/alpha/ucontext-offsets.sym
index f95ff75636..9e86f8a7ca 100644
--- a/sysdeps/unix/sysv/linux/alpha/ucontext-offsets.sym
+++ b/sysdeps/unix/sysv/linux/alpha/ucontext-offsets.sym
@@ -7,12 +7,12 @@ UC_OSF_SIGMASK	offsetof (ucontext_t, __uc_osf_sigmask)
 UC_STACK	offsetof (ucontext_t, uc_stack)
 UC_SIGCTX	offsetof (ucontext_t, uc_mcontext)
 UC_SIGMASK	offsetof (ucontext_t, uc_sigmask)
-SC_REGS		offsetof (struct sigcontext, sc_regs)
-SC_FPREGS	offsetof (struct sigcontext, sc_fpregs)
-SC_PC		offsetof (struct sigcontext, sc_pc)
-SC_PS		offsetof (struct sigcontext, sc_ps)
-SC_FPCRS	offsetof (struct sigcontext, sc_fpcr)
-SC_MASK		offsetof (struct sigcontext, sc_mask)
-SC_FPCR		offsetof (struct sigcontext, sc_fpcr)
+SC_REGS		offsetof (mcontext_t, sc_regs)
+SC_FPREGS	offsetof (mcontext_t, sc_fpregs)
+SC_PC		offsetof (mcontext_t, sc_pc)
+SC_PS		offsetof (mcontext_t, sc_ps)
+SC_FPCRS	offsetof (mcontext_t, sc_fpcr)
+SC_MASK		offsetof (mcontext_t, sc_mask)
+SC_FPCR		offsetof (mcontext_t, sc_fpcr)
 SS_SP		offsetof (stack_t, ss_sp)
 SS_SIZE		offsetof (stack_t, ss_size)
diff --git a/sysdeps/unix/sysv/linux/arm/sys/ucontext.h b/sysdeps/unix/sysv/linux/arm/sys/ucontext.h
index 2abceef2a4..192d1bdeac 100644
--- a/sysdeps/unix/sysv/linux/arm/sys/ucontext.h
+++ b/sysdeps/unix/sysv/linux/arm/sys/ucontext.h
@@ -23,11 +23,16 @@