File math-c++-compat.patch of Package glibc.10713
2017-10-17 Romain Naour <romain.naour@gmail.com> (tiny change)
[BZ #22296]
* math/math.h: Let signbit use the builtin in C++ mode with gcc
< 6.x
2017-10-03 Gabriel F. T. Gomes <gabriel@inconstante.eti.br>
[BZ #22235]
* sysdeps/ieee754/ldbl-96/bits/iscanonical.h (iscanonical):
Provide a C++ implementation based on function overloading,
rather than using __MATH_TG, which uses C-only builtins.
* sysdeps/ieee754/ldbl-128ibm/bits/iscanonical.h (iscanonical):
Likewise.
2017-09-22 Gabriel F. T. Gomes <gabriel@inconstante.eti.br>
[BZ #22146]
math/math.h: Let fpclassify use the builtin in C++ mode, even
when optimazing for size.
2017-08-28 Gabriel F. T. Gomes <gftg@linux.vnet.ibm.com>
[BZ #21930]
* math/math.h [defined __cplusplus && defined __SUPPORT_SNAN__]
(iszero): New C++ implementation that does not use
fpclassify/__MATH_TG/__builtin_types_compatible_p, when
signaling nans are enabled, since __builtin_types_compatible_p
is a C-only feature.
2017-08-24 Gabriel F. T. Gomes <gftg@linux.vnet.ibm.com>
* math/math.h [defined __cplusplus] (issignaling): In the long
double case, call __issignalingl only if __NO_LONG_DOUBLE_MATH
is not defined. Call __issignaling, otherwise.
2017-08-22 Gabriel F. T. Gomes <gftg@linux.vnet.ibm.com>
* math/math.h [defined __cplusplus] (issignaling): Provide a C++
definition for issignaling that does not rely on __MATH_TG,
since __MATH_TG uses __builtin_types_compatible_p, which is only
available in C mode.
2017-08-18 Gabriel F. T. Gomes <gftg@linux.vnet.ibm.com>
[BZ #21930]
* math/math.h (isinf): Check if in C or C++ mode before using
__builtin_types_compatible_p, since this is a C mode feature.
2017-08-18 Gabriel F. T. Gomes <gftg@linux.vnet.ibm.com>
* misc/sys/cdefs.h (__HAVE_GENERIC_SELECTION): Define to 0, if
in C++ mode.
Index: glibc-2.26/math/math.h
===================================================================
--- glibc-2.26.orig/math/math.h
+++ glibc-2.26/math/math.h
@@ -402,7 +402,13 @@ enum
/* Return number of classification appropriate for X. */
# if __GNUC_PREREQ (4,4) && !defined __SUPPORT_SNAN__ \
- && !defined __OPTIMIZE_SIZE__
+ && (!defined __OPTIMIZE_SIZE__ || defined __cplusplus)
+ /* The check for __cplusplus allows the use of the builtin, even
+ when optimization for size is on. This is provided for
+ libstdc++, only to let its configure test work when it is built
+ with -Os. No further use of this definition of fpclassify is
+ expected in C++ mode, since libstdc++ provides its own version
+ of fpclassify in cmath (which undefines fpclassify). */
# define fpclassify(x) __builtin_fpclassify (FP_NAN, FP_INFINITE, \
FP_NORMAL, FP_SUBNORMAL, FP_ZERO, x)
# else
@@ -412,6 +418,15 @@ enum
/* Return nonzero value if sign of X is negative. */
# if __GNUC_PREREQ (6,0)
# define signbit(x) __builtin_signbit (x)
+# elif defined __cplusplus
+ /* In C++ mode, __MATH_TG cannot be used, because it relies on
+ __builtin_types_compatible_p, which is a C-only builtin.
+ The check for __cplusplus allows the use of the builtin instead of
+ __MATH_TG. This is provided for libstdc++, only to let its configure
+ test work. No further use of this definition of signbit is expected
+ in C++ mode, since libstdc++ provides its own version of signbit
+ in cmath (which undefines signbit). */
+# define signbit(x) __builtin_signbitl (x)
# elif __GNUC_PREREQ (4,0)
# define signbit(x) __MATH_TG ((x), __builtin_signbit, (x))
# else
@@ -442,8 +457,12 @@ enum
/* Return nonzero value if X is positive or negative infinity. */
# if __HAVE_DISTINCT_FLOAT128 && !__GNUC_PREREQ (7,0) \
- && !defined __SUPPORT_SNAN__
- /* __builtin_isinf_sign is broken for float128 only before GCC 7.0. */
+ && !defined __SUPPORT_SNAN__ && !defined __cplusplus
+ /* Since __builtin_isinf_sign is broken for float128 before GCC 7.0,
+ use the helper function, __isinff128, with older compilers. This is
+ only provided for C mode, because in C++ mode, GCC has no support
+ for __builtin_types_compatible_p (and when in C++ mode, this macro is
+ not used anyway, because libstdc++ headers undefine it). */
# define isinf(x) \
(__builtin_types_compatible_p (__typeof (x), _Float128) \
? __isinff128 (x) : __builtin_isinf_sign (x))
@@ -470,7 +489,32 @@ enum
# include <bits/iscanonical.h>
/* Return nonzero value if X is a signaling NaN. */
-# define issignaling(x) __MATH_TG ((x), __issignaling, (x))
+# ifndef __cplusplus
+# define issignaling(x) __MATH_TG ((x), __issignaling, (x))
+# else
+ /* In C++ mode, __MATH_TG cannot be used, because it relies on
+ __builtin_types_compatible_p, which is a C-only builtin. On the
+ other hand, overloading provides the means to distinguish between
+ the floating-point types. The overloading resolution will match
+ the correct parameter (regardless of type qualifiers (i.e.: const
+ and volatile). */
+extern "C++" {
+inline int issignaling (float __val) { return __issignalingf (__val); }
+inline int issignaling (double __val) { return __issignaling (__val); }
+inline int
+issignaling (long double __val)
+{
+# ifdef __NO_LONG_DOUBLE_MATH
+ return __issignaling (__val);
+# else
+ return __issignalingl (__val);
+# endif
+}
+# if __HAVE_DISTINCT_FLOAT128
+inline int issignaling (_Float128 __val) { return __issignalingf128 (__val); }
+# endif
+} /* extern C++ */
+# endif
/* Return nonzero value if X is subnormal. */
# define issubnormal(x) (fpclassify (x) == FP_SUBNORMAL)
@@ -484,15 +528,40 @@ enum
# endif
# else /* __cplusplus */
extern "C++" {
+# ifdef __SUPPORT_SNAN__
+inline int
+iszero (float __val)
+{
+ return __fpclassifyf (__val) == FP_ZERO;
+}
+inline int
+iszero (double __val)
+{
+ return __fpclassify (__val) == FP_ZERO;
+}
+inline int
+iszero (long double __val)
+{
+# ifdef __NO_LONG_DOUBLE_MATH
+ return __fpclassify (__val) == FP_ZERO;
+# else
+ return __fpclassifyl (__val) == FP_ZERO;
+# endif
+}
+# if __HAVE_DISTINCT_FLOAT128
+inline int
+iszero (_Float128 __val)
+{
+ return __fpclassifyf128 (__val) == FP_ZERO;
+}
+# endif
+# else
template <class __T> inline bool
iszero (__T __val)
{
-# ifdef __SUPPORT_SNAN__
- return fpclassify (__val) == FP_ZERO;
-# else
return __val == 0;
-# endif
}
+# endif
} /* extern C++ */
# endif /* __cplusplus */
#endif /* Use IEC_60559_BFP_EXT. */
Index: glibc-2.26/misc/sys/cdefs.h
===================================================================
--- glibc-2.26.orig/misc/sys/cdefs.h
+++ glibc-2.26/misc/sys/cdefs.h
@@ -464,17 +464,18 @@
# define __glibc_macro_warning(msg)
#endif
-/* Support for generic selection (ISO C11) is available in GCC since
- version 4.9. Previous versions do not provide generic selection,
- even though they might set __STDC_VERSION__ to 201112L, when in
- -std=c11 mode. Thus, we must check for !defined __GNUC__ when
- testing __STDC_VERSION__ for generic selection support.
+/* Generic selection (ISO C11) is a C-only feature, available in GCC
+ since version 4.9. Previous versions do not provide generic
+ selection, even though they might set __STDC_VERSION__ to 201112L,
+ when in -std=c11 mode. Thus, we must check for !defined __GNUC__
+ when testing __STDC_VERSION__ for generic selection support.
On the other hand, Clang also defines __GNUC__, so a clang-specific
check is required to enable the use of generic selection. */
-#if __GNUC_PREREQ (4, 9) \
- || __glibc_clang_has_extension (c_generic_selections) \
- || (!defined __GNUC__ && defined __STDC_VERSION__ \
- && __STDC_VERSION__ >= 201112L)
+#if !defined __cplusplus \
+ && (__GNUC_PREREQ (4, 9) \
+ || __glibc_clang_has_extension (c_generic_selections) \
+ || (!defined __GNUC__ && defined __STDC_VERSION__ \
+ && __STDC_VERSION__ >= 201112L))
# define __HAVE_GENERIC_SELECTION 1
#else
# define __HAVE_GENERIC_SELECTION 0
Index: glibc-2.26/sysdeps/ieee754/ldbl-128ibm/bits/iscanonical.h
===================================================================
--- glibc-2.26.orig/sysdeps/ieee754/ldbl-128ibm/bits/iscanonical.h
+++ glibc-2.26/sysdeps/ieee754/ldbl-128ibm/bits/iscanonical.h
@@ -37,5 +37,22 @@ extern int __iscanonicall (long double _
conversion, before being discarded; in IBM long double, there are
encodings that are not consistently handled as corresponding to any
particular value of the type, and we return 0 for those. */
-# define iscanonical(x) __MATH_TG ((x), __iscanonical, (x))
-#endif
+# ifndef __cplusplus
+# define iscanonical(x) __MATH_TG ((x), __iscanonical, (x))
+# else
+/* In C++ mode, __MATH_TG cannot be used, because it relies on
+ __builtin_types_compatible_p, which is a C-only builtin. On the
+ other hand, overloading provides the means to distinguish between
+ the floating-point types. The overloading resolution will match
+ the correct parameter (regardless of type qualifiers (i.e.: const
+ and volatile)). */
+extern "C++" {
+inline int iscanonical (float __val) { return __iscanonicalf (__val); }
+inline int iscanonical (double __val) { return __iscanonical (__val); }
+inline int iscanonical (long double __val) { return __iscanonicall (__val); }
+# if __HAVE_DISTINCT_FLOAT128
+inline int iscanonical (_Float128 __val) { return __iscanonicalf128 (__val); }
+# endif
+}
+# endif /* __cplusplus */
+#endif /* __NO_LONG_DOUBLE_MATH */
Index: glibc-2.26/sysdeps/ieee754/ldbl-96/bits/iscanonical.h
===================================================================
--- glibc-2.26.orig/sysdeps/ieee754/ldbl-96/bits/iscanonical.h
+++ glibc-2.26/sysdeps/ieee754/ldbl-96/bits/iscanonical.h
@@ -34,4 +34,21 @@ extern int __iscanonicall (long double _
conversion, before being discarded; in extended precision, there
are encodings that are not consistently handled as corresponding to
any particular value of the type, and we return 0 for those. */
-#define iscanonical(x) __MATH_TG ((x), __iscanonical, (x))
+#ifndef __cplusplus
+# define iscanonical(x) __MATH_TG ((x), __iscanonical, (x))
+#else
+/* In C++ mode, __MATH_TG cannot be used, because it relies on
+ __builtin_types_compatible_p, which is a C-only builtin. On the
+ other hand, overloading provides the means to distinguish between
+ the floating-point types. The overloading resolution will match
+ the correct parameter (regardless of type qualifiers (i.e.: const
+ and volatile)). */
+extern "C++" {
+inline int iscanonical (float __val) { return __iscanonicalf (__val); }
+inline int iscanonical (double __val) { return __iscanonical (__val); }
+inline int iscanonical (long double __val) { return __iscanonicall (__val); }
+# if __HAVE_DISTINCT_FLOAT128
+inline int iscanonical (_Float128 __val) { return __iscanonicalf128 (__val); }
+# endif
+}
+#endif /* __cplusplus */
