Define TS 18661-1 type width macros in <limits.h> and <stdint.h>.

TS 18661-1 defines <limits.h> and <stdint.h> macros for widths of
standard integer types and the typedefs defined in, or whose limits
are defined in, <stdint.h>.  (The connection to the main
floating-point subject matter of TS 18661-1 is that these are intended
to be used with the fromfp functions to convert from floating point to
integer types of any width in any rounding direction, though these
macros may be of more general use.)

This patch implements support for these macros in GCC's <limits.h> and
<stdint.h>.  To avoid needing to implement fixincludes for system
headers where GCC wraps the system libc's <stdint.h> in hosted mode,
the test for the <stdint.h> macros uses -ffreestanding (I'll add the
macros to glibc's headers separately) - but as usual for new features
in these headers, platforms (primarily OpenBSD) that use USER_H to
avoid using GCC's headers at all will have failures until the system
headers have the feature added or appropriate fixincludes are
implemented.

The header macros are implemented using appropriate new predefined
macros, with the code avoiding defining more such macros than
necessary (so one predefined macro suffices for corresponding signed
and unsigned types, while no such predefined macros are needed for the
exact-width types such as int8_t).

Bootstrapped with no regressions on x86_64-pc-linux-gnu.

gcc:
	* doc/cpp.texi (__SCHAR_WIDTH__, __SHRT_WIDTH__, __INT_WIDTH__)
	(__LONG_WIDTH__, __LONG_LONG_WIDTH__, __PTRDIFF_WIDTH__)
	(__SIG_ATOMIC_WIDTH__, __SIZE_WIDTH__, __WCHAR_WIDTH__)
	(__WINT_WIDTH__, __INT_LEAST8_WIDTH__, __INT_LEAST16_WIDTH__)
	(__INT_LEAST32_WIDTH__, __INT_LEAST64_WIDTH__)
	(__INT_FAST8_WIDTH__, __INT_FAST16_WIDTH__, __INT_FAST32_WIDTH__)
	(__INT_FAST64_WIDTH__, __INTPTR_WIDTH__, __INTMAX_WIDTH__):
	Document.
	* ginclude/stdint-gcc.h [__STDC_WANT_IEC_60559_BFP_EXT__]: Define
	width macros from TS 18661-1.
	* glimits.h [__STDC_WANT_IEC_60559_BFP_EXT__]: Likewise.

gcc/c-family:
	* c-cppbuiltin.c (builtin_define_type_width): New function.
	(builtin_define_stdint_macros, c_cpp_builtins): Define type width
	macros.

gcc/testsuite:
	* gcc.dg/limits-width-1.c, gcc.dg/stdint-width-1.c: New tests.

From-SVN: r240048

1 files changed, 175 insertions, 0 deletions

diff --git a/gcc/testsuite/gcc.dg/stdint-width-1.c b/gcc/testsuite/gcc.dg/stdint-width-1.c
new file mode 100644
index 0000000..a28feee
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/stdint-width-1.c
@@ -0,0 +1,175 @@
+/* Test TS 18661-1 width macros in <stdint.h>.  */
+/* { dg-do compile } */
+/* { dg-options "-std=c11 -ffreestanding" } */
+
+#include <stddef.h>
+#define __STDC_WANT_IEC_60559_BFP_EXT__
+#include <stdint.h>
+#ifndef SIGNAL_SUPPRESS
+#include <signal.h>
+#endif
+typedef __WINT_TYPE__ wint_t;
+
+#define CHECK_WIDTH(TYPE, MAX, WIDTH)					\
+  _Static_assert ((MAX >> ((TYPE) -1 < 0 ? (WIDTH - 2) : (WIDTH - 1))) == 1, \
+		  "width must match type")
+
+#ifdef INT8_MAX
+# ifndef INT8_WIDTH
+#  error "missing INT8_WIDTH"
+# endif
+CHECK_WIDTH (int8_t, INT8_MAX, INT8_WIDTH);
+#endif
+#ifdef INT16_MAX
+# ifndef INT16_WIDTH
+#  error "missing INT16_WIDTH"
+# endif
+CHECK_WIDTH (int16_t, INT16_MAX, INT16_WIDTH);
+#endif
+#ifdef INT32_MAX
+# ifndef INT32_WIDTH
+#  error "missing INT32_WIDTH"
+# endif
+CHECK_WIDTH (int32_t, INT32_MAX, INT32_WIDTH);
+#endif
+#ifdef INT64_MAX
+# ifndef INT64_WIDTH
+#  error "missing INT64_WIDTH"
+# endif
+CHECK_WIDTH (int64_t, INT64_MAX, INT64_WIDTH);
+#endif
+#ifdef UINT8_MAX
+# ifndef UINT8_WIDTH
+#  error "missing UINT8_WIDTH"
+# endif
+CHECK_WIDTH (uint8_t, UINT8_MAX, UINT8_WIDTH);
+#endif
+#ifdef UINT16_MAX
+# ifndef UINT16_WIDTH
+#  error "missing UINT16_WIDTH"
+# endif
+CHECK_WIDTH (uint16_t, UINT16_MAX, UINT16_WIDTH);
+#endif
+#ifdef UINT32_MAX
+# ifndef UINT32_WIDTH
+#  error "missing UINT32_WIDTH"
+# endif
+CHECK_WIDTH (uint32_t, UINT32_MAX, UINT32_WIDTH);
+#endif
+#ifdef UINT64_MAX
+# ifndef UINT64_WIDTH
+#  error "missing UINT64_WIDTH"
+# endif
+CHECK_WIDTH (uint64_t, UINT64_MAX, UINT64_WIDTH);
+#endif
+
+#ifndef INT_LEAST8_WIDTH
+# error "missing INT_LEAST8_WIDTH"
+#endif
+CHECK_WIDTH (int_least8_t, INT_LEAST8_MAX, INT_LEAST8_WIDTH);
+#ifndef INT_LEAST16_WIDTH
+# error "missing INT_LEAST16_WIDTH"
+#endif
+CHECK_WIDTH (int_least16_t, INT_LEAST16_MAX, INT_LEAST16_WIDTH);
+#ifndef INT_LEAST32_WIDTH
+# error "missing INT_LEAST32_WIDTH"
+#endif
+CHECK_WIDTH (int_least32_t, INT_LEAST32_MAX, INT_LEAST32_WIDTH);
+#ifndef INT_LEAST64_WIDTH
+# error "missing INT_LEAST64_WIDTH"
+#endif
+CHECK_WIDTH (int_least64_t, INT_LEAST64_MAX, INT_LEAST64_WIDTH);
+#ifndef INT_LEAST8_WIDTH
+# error "missing INT_LEAST8_WIDTH"
+#endif
+CHECK_WIDTH (uint_least8_t, UINT_LEAST8_MAX, UINT_LEAST8_WIDTH);
+#ifndef UINT_LEAST16_WIDTH
+# error "missing UINT_LEAST16_WIDTH"
+#endif
+CHECK_WIDTH (uint_least16_t, UINT_LEAST16_MAX, UINT_LEAST16_WIDTH);
+#ifndef UINT_LEAST32_WIDTH
+# error "missing UINT_LEAST32_WIDTH"
+#endif
+CHECK_WIDTH (uint_least32_t, UINT_LEAST32_MAX, UINT_LEAST32_WIDTH);
+#ifndef UINT_LEAST64_WIDTH
+# error "missing UINT_LEAST64_WIDTH"
+#endif
+CHECK_WIDTH (uint_least64_t, UINT_LEAST64_MAX, UINT_LEAST64_WIDTH);
+
+#ifndef INT_FAST8_WIDTH
+# error "missing INT_FAST8_WIDTH"
+#endif
+CHECK_WIDTH (int_fast8_t, INT_FAST8_MAX, INT_FAST8_WIDTH);
+#ifndef INT_FAST16_WIDTH
+# error "missing INT_FAST16_WIDTH"
+#endif
+CHECK_WIDTH (int_fast16_t, INT_FAST16_MAX, INT_FAST16_WIDTH);
+#ifndef INT_FAST32_WIDTH
+# error "missing INT_FAST32_WIDTH"
+#endif
+CHECK_WIDTH (int_fast32_t, INT_FAST32_MAX, INT_FAST32_WIDTH);
+#ifndef INT_FAST64_WIDTH
+# error "missing INT_FAST64_WIDTH"
+#endif
+CHECK_WIDTH (int_fast64_t, INT_FAST64_MAX, INT_FAST64_WIDTH);
+#ifndef INT_FAST8_WIDTH
+# error "missing INT_FAST8_WIDTH"
+#endif
+CHECK_WIDTH (uint_fast8_t, UINT_FAST8_MAX, UINT_FAST8_WIDTH);
+#ifndef UINT_FAST16_WIDTH
+# error "missing UINT_FAST16_WIDTH"
+#endif
+CHECK_WIDTH (uint_fast16_t, UINT_FAST16_MAX, UINT_FAST16_WIDTH);
+#ifndef UINT_FAST32_WIDTH
+# error "missing UINT_FAST32_WIDTH"
+#endif
+CHECK_WIDTH (uint_fast32_t, UINT_FAST32_MAX, UINT_FAST32_WIDTH);
+#ifndef UINT_FAST64_WIDTH
+# error "missing UINT_FAST64_WIDTH"
+#endif
+CHECK_WIDTH (uint_fast64_t, UINT_FAST64_MAX, UINT_FAST64_WIDTH);
+
+#ifdef INTPTR_MAX
+# ifndef INTPTR_WIDTH
+#  error "missing INTPTR_WIDTH"
+# endif
+CHECK_WIDTH (intptr_t, INTPTR_MAX, INTPTR_WIDTH);
+#endif
+#ifdef UINTPTR_MAX
+# ifndef UINTPTR_WIDTH
+#  error "missing UINTPTR_WIDTH"
+# endif
+CHECK_WIDTH (uintptr_t, UINTPTR_MAX, UINTPTR_WIDTH);
+#endif
+
+#ifndef INTMAX_WIDTH
+# error "missing INTMAX_WIDTH"
+#endif
+CHECK_WIDTH (intmax_t, INTMAX_MAX, INTMAX_WIDTH);
+#ifndef UINTMAX_WIDTH
+# error "missing UINTMAX_WIDTH"
+#endif
+CHECK_WIDTH (uintmax_t, UINTMAX_MAX, UINTMAX_WIDTH);
+
+#ifndef PTRDIFF_WIDTH
+# error "missing PTRDIFF_WIDTH"
+#endif
+CHECK_WIDTH (ptrdiff_t, PTRDIFF_MAX, PTRDIFF_WIDTH);
+#ifndef SIGNAL_SUPPRESS
+# ifndef SIG_ATOMIC_WIDTH
+#  error "missing SIG_ATOMIC_WIDTH"
+# endif
+CHECK_WIDTH (sig_atomic_t, SIG_ATOMIC_MAX, SIG_ATOMIC_WIDTH);
+#endif
+#ifndef SIZE_WIDTH
+# error "missing SIZE_WIDTH"
+#endif
+CHECK_WIDTH (size_t, SIZE_MAX, SIZE_WIDTH);
+#ifndef WCHAR_WIDTH
+# error "missing WCHAR_WIDTH"
+#endif
+CHECK_WIDTH (wchar_t, WCHAR_MAX, WCHAR_WIDTH);
+#ifndef WINT_WIDTH
+# error "missing WINT_WIDTH"
+#endif
+CHECK_WIDTH (wint_t, WINT_MAX, WINT_WIDTH);