Fix more namespace issues in sys/ucontext.h (bug 21457).

Continuing the fixes for namespace issues in sys/ucontext.h, this
patch moves various symbols into the implementation namespace in the
absence of __USE_MISC.  As with previous changes, it is nonexhaustive,
just covering more straightforward cases.

Structure fields are generally changed to have a prefix __ in the
absence of __USE_MISC, via a macro __ctx (used without a space before
the open parenthesis, since the result is a single identifier).
Various macros such as NGREG also have leading __ added.  No changes
are made to structure tags (and thus to C++ name mangling), except
that in the (unused) file sysdeps/i386/sys/ucontext.h, structures
defined inside other structures as the type for a field have their
tags removed in the non-__USE_MISC case (those structure tags would
not in any case have been visible in C++, because in C++ the scope of
such a tag is limited to the containing structure).  No changes are
made to the contents of bits/sigcontext.h, or to whether it is
included.  Because of remaining namespace issues, this patch does not
yet fix the bug or allow any XFAILs to be removed.

Tested for x86_64 and x86, and with build-many-glibcs.py.

	[BZ #21457]
	* sysdeps/arm/sys/ucontext.h (NGREG): Rename to __NGREG and define
	NGREG to __NGREG if [__USE_MISC].
	(gregset_t): Define using __NGREG.
	(__ctx): New macro.
	(mcontext_t): Use __ctx in defining fields.
	* sysdeps/i386/sys/ucontext.h (NGREG): Rename to __NGREG and
	define NGREG to __NGREG if [__USE_MISC].
	(gregset_t): Define using __NGREG.
	(__ctx): New macro.
	(__ctxt): Likewise.
	(fpregset_t): Use __ctx and __ctxt in defining fields.
	(mcontext_t): Likewise.
	* sysdeps/m68k/sys/ucontext.h (NGREG): Rename to __NGREG and
	define NGREG to __NGREG if [__USE_MISC].
	(gregset_t): Define using __NGREG.
	(__ctx): New macro.
	(mcontext_t): Use __ctx in defining fields.
	* sysdeps/mips/sys/ucontext.h (NGREG): Rename to __NGREG and
	define NGREG to __NGREG if [__USE_MISC].
	(gregset_t): Define using __NGREG.
	(__ctx): New macro.
	(fpregset_t): Use __ctx in defining fields.
	(mcontext_t): Likewise.
	* sysdeps/unix/sysv/linux/alpha/sys/ucontext.h (NGREG): Rename to
	__NGREG and define NGREG to __NGREG if [__USE_MISC].
	(gregset_t): Define using __NGREG.
	(NFPREG): Rename to __NFPREG and define NFPREG to __NFPREG if
	[__USE_MISC].
	(fpregset_t): Define using __NFPREG.
	* sysdeps/unix/sysv/linux/m68k/sys/ucontext.h (NGREG): Rename to
	__NGREG and define NGREG to __NGREG if [__USE_MISC].
	(gregset_t): Define using __NGREG.
	(__ctx): New macro.
	(fpregset_t): Use __ctx in defining fields.
	(mcontext_t): Likewise.
	* sysdeps/unix/sysv/linux/mips/sys/ucontext.h (NGREG): Rename to
	__NGREG and define NGREG to __NGREG if [__USE_MISC].
	(NFPREG): Rename to __NFPREG and define NFPREG to __NFPREG if
	[__USE_MISC].
	(gregset_t): Define using __NGREG.
	(__ctx): New macro.
	(fpregset_t): Use __ctx in defining fields.
	(mcontext_t): Likewise.
	* sysdeps/unix/sysv/linux/nios2/sys/ucontext.h (__ctx): New macro.
	(mcontext_t): Use __ctx in defining fields.
	* sysdeps/unix/sysv/linux/powerpc/sys/ucontext.h (__ctx): New
	macro.
	[__WORDSIZE == 32] (NGREG): Rename to __NGREG and define NGREG to
	__NGREG if [__USE_MISC].
	[__WORDSIZE == 32] (gregset_t): Define using __NGREG.
	[__WORDSIZE == 32] (fpregset_t): Use __ctx in defining fields.
	(mcontext_t): Likewise.
	[__WORDSIZE != 32] (NGREG): Rename to __NGREG and define NGREG to
	__NGREG if [__USE_MISC].
	[__WORDSIZE != 32] (NFPREG): Rename to __NFPREG and define NFPREG
	to __NFPREG if [__USE_MISC].
	[__WORDSIZE != 32] (NVRREG): Rename to __NVRREG and define NVRREG
	to __NVRREG if [__USE_MISC].
	[__WORDSIZE != 32] (gregset_t): Define using __NGREG.
	[__WORDSIZE != 32] (fpregset_t): Define using __NFPREG.
	[__WORDSIZE != 32] (vscr_t): Use __ctx in defining fields.
	[__WORDSIZE != 32] (vrregset_t): Likewise.
	[__WORDSIZE != 32] (mcontext_t): Likewise.
	* sysdeps/unix/sysv/linux/s390/sys/ucontext.h (__ctx): New macro.
	(__psw_t): Use __ctx in defining fields.
	(NGREG): Rename to __NGREG and define NGREG to __NGREG if
	[__USE_MISC].
	(gregset_t): Define using __NGREG.
	(fpreg_t): Use __ctx in defining fields.
	(fpregset_t): Likewise.
	(mcontext_t): Likewise.
	* sysdeps/unix/sysv/linux/sh/sys/ucontext.h (NGREG): Rename to
	__NGREG and define NGREG to __NGREG if [__USE_MISC].
	(gregset_t): Define using __NGREG.
	(NFPREG): Rename to __NFPREG and define NFPREG to __NFPREG if
	[__USE_MISC].
	(fpregset_t): Define using __NFPREG.
	(__ctx): New macro.
	(mcontext_t): Use __ctx in defining fields.
	* sysdeps/unix/sysv/linux/x86/sys/ucontext.h (__ctx): New macro.
	[__x86_64__] (NGREG): Rename to __NGREG and define NGREG to
	__NGREG if [__USE_MISC].
	[__x86_64__] (gregset_t): Define using __NGREG.
	[__x86_64__] (struct _libc_fpxreg): Use __ctx in defining fields.
	[__x86_64__] (struct _libc_fpstate): Likewise.
	[__x86_64__] (mcontext_t): Likewise.
	[!__x86_64__] (NGREG): Rename to __NGREG and define NGREG to
	__NGREG if [__USE_MISC].
	[!__x86_64__] (gregset_t): Define using __NGREG.
	[!__x86_64__] (struct _libc_fpreg): Use __ctx in defining fields.
	[!__x86_64__] (struct _libc_fpstate): Likewise.
	[!__x86_64__] (mcontext_t): Likewise.

1 files changed, 29 insertions, 15 deletions

diff --git a/sysdeps/i386/sys/ucontext.h b/sysdeps/i386/sys/ucontext.h
index a6b936a..fb5df11 100644
--- a/sysdeps/i386/sys/ucontext.h
+++ b/sysdeps/i386/sys/ucontext.h
@@ -31,10 +31,13 @@
 typedef int greg_t;
 
 /* Number of general registers.  */
-#define NGREG	19
+#define __NGREG	19
+#ifdef __USE_MISC
+# define NGREG	__NGREG
+#endif
 
 /* Container for all general registers.  */
-typedef greg_t gregset_t[NGREG];
+typedef greg_t gregset_t[__NGREG];
 
 #ifdef __USE_MISC
 /* Number of each register is the `gregset_t' array.  */
@@ -81,36 +84,47 @@ enum
 };
 #endif
 
+#ifdef __USE_MISC
+# define __ctx(fld) fld
+# define __ctxt(tag) tag
+#else
+# define __ctx(fld) __ ## fld
+# define __ctxt(tag) /* Empty.  */
+#endif
+
 /* Structure to describe FPU registers.  */
 typedef struct fpregset
   {
     union
       {
-	struct fpchip_state
+	struct __ctxt(fpchip_state)
 	  {
-	    int state[27];
-	    int status;
-	  } fpchip_state;
+	    int __ctx(state)[27];
+	    int __ctx(status);
+	  } __ctx(fpchip_state);
 
-	struct fp_emul_space
+	struct __ctxt(fp_emul_space)
 	  {
-	    char fp_emul[246];
-	    char fp_epad[2];
-	  } fp_emul_space;
+	    char __ctx(fp_emul)[246];
+	    char __ctx(fp_epad)[2];
+	  } __ctx(fp_emul_space);
 
-	int f_fpregs[62];
-      } fp_reg_set;
+	int __ctx(f_fpregs)[62];
+      } __ctx(fp_reg_set);
 
-    long int f_wregs[33];
+    long int __ctx(f_wregs)[33];
   } fpregset_t;
 
 /* Context to describe whole processor state.  */
 typedef struct
   {
-    gregset_t gregs;
-    fpregset_t fpregs;
+    gregset_t __ctx(gregs);
+    fpregset_t __ctx(fpregs);
   } mcontext_t;
 
+#undef __ctx
+#undef __ctxt
+
 /* Userlevel context.  */
 typedef struct ucontext
   {