fix C++ std::abs

Author: ZERICO2005

src/libc/include/__cxx_abs.h

@@ -0,0 +1,30 @@
+#ifndef _CXX_ABS_H
+#define _CXX_ABS_H
+
+#include <__stdlib_abs.h>
+#include <__math_abs.h>
+
+#pragma clang system_header
+
+// https://cplusplus.github.io/LWG/issue2192
+
+namespace std {
+using ::abs;
+
+inline constexpr long abs(long __x) { return labs(__x); }
+
+#ifdef __SIZEOF_INT48__
+inline signed __int48 abs(signed __int48 __x) { return i48abs(__x); }
+#endif // __SIZEOF_INT48__
+
+inline constexpr long long abs(long long __x) { return llabs(__x); }
+
+inline constexpr float abs(float __x) { return fabsf(__x); }
+
+inline constexpr double abs(double __x) { return fabs(__x); }
+
+inline constexpr long double abs(long double __x) { return fabsl(__x); }
+
+} // namespace std
+
+#endif /* _CXX_ABS_H */

src/libc/include/__math_abs.h

@@ -0,0 +1,16 @@
+#ifndef _MATH_ABS_H
+#define _MATH_ABS_H
+
+#include <cdefs.h>
+
+__BEGIN_DECLS
+
+float fabsf(float);
+
+double fabs(double);
+
+long double fabsl(long double);
+
+__END_DECLS
+
+#endif /* _MATH_ABS_H */

src/libc/include/__math_def.h

@@ -3,6 +3,11 @@
 
 #include <cdefs.h>
 #include <stdbool.h>
+#include <__math_abs.h>
+
+#ifdef __cplusplus
+#include <__cxx_abs.h>
+#endif /* __cplusplus */
 
 #define NAN          __builtin_nanf("")
 #define INFINITY     __builtin_inff()
@@ -37,9 +42,7 @@
 typedef float float_t;
 typedef double double_t;
 
-#ifdef __cplusplus
-extern "C" {
-#endif
+__BEGIN_DECLS
 
 int _fpclassifyf(float) __NOEXCEPT_CONST;
 int _fpclassifyl(long double) __NOEXCEPT_CONST;
@@ -141,13 +144,6 @@ double      expm1(double);
 float       expm1f(float);
 long double expm1l(long double);
 
-#ifndef _ABS_FLOAT_DEFINED
-#define _ABS_FLOAT_DEFINED
-double      fabs(double);
-float       fabsf(float);
-long double fabsl(long double);
-#endif /* _ABS_FLOAT_DEFINED */
-
 double      fdim(double, double);
 float       fdimf(float, float);
 long double fdiml(long double, long double);
@@ -328,8 +324,6 @@ double      trunc(double);
 float       truncf(float);
 long double truncl(long double);
 
-#ifdef __cplusplus
-}
-#endif
+__END_DECLS
 
 #endif /* _MATH_DEF_H */

src/libc/include/__stdlib_abs.h

@@ -0,0 +1,20 @@
+#ifndef _STDLIB_ABS_H
+#define _STDLIB_ABS_H
+
+#include <cdefs.h>
+
+__BEGIN_DECLS
+
+int abs(int);
+
+long labs(long);
+
+#ifdef __SIZEOF_INT48__
+signed __int48 i48abs(signed __int48 n) __NOEXCEPT_CONST;
+#endif /* __SIZEOF_INT48__ */
+
+long long llabs(long long);
+
+__END_DECLS
+
+#endif /* _STDLIB_ABS_H */

src/libc/include/inttypes.h

@@ -4,6 +4,10 @@
 #include <cdefs.h>
 #include <stdint.h>
 
+#ifdef __cplusplus
+#include <__cxx_abs.h>
+#endif /* __cplusplus */
+
 #define PRId8               __INT8_FMTd__
 #define PRIi8               __INT8_FMTi__
 #define PRIo8              __UINT8_FMTo__

src/libc/include/stdlib.h

@@ -2,6 +2,11 @@
 #define _STDLIB_H
 
 #include <cdefs.h>
+#include <__stdlib_abs.h>
+
+#ifdef __cplusplus
+#include <__cxx_abs.h>
+#endif /* __cplusplus */
 
 typedef struct {
     int quot;
@@ -100,19 +105,6 @@ void quick_exit(int) __NOEXCEPT __attribute__((noreturn));
 
 void _Exit(int) __NOEXCEPT __attribute__((noreturn));
 
-#ifndef _ABS_INT_DEFINED
-#define _ABS_INT_DEFINED
-
-int abs(int n);
-long labs(long n);
-long long llabs(long long n);
-
-#ifdef __SIZEOF_INT48__
-signed __int48 i48abs(signed __int48 n) __NOEXCEPT_CONST;
-#endif /* __SIZEOF_INT48__ */
-
-#endif /* _ABS_INT_DEFINED */
-
 div_t div(int numer, int denom);
 
 ldiv_t ldiv(long numer, long denom);

src/libcxx/include/__abs_overloads

@@ -4,7 +4,6 @@
 
 #include <__math_def.h>
 #include <__cmath_type_traits>
-#include <__abs_overloads>
 
 #pragma clang system_header
 

src/libcxx/include/cmath

@@ -3,7 +3,6 @@
 #define _EZCXX_CSTDLIB
 
 #include <stdlib.h>
-#include <__abs_overloads>
 
 #pragma clang system_header
 
@@ -41,6 +40,9 @@ using ::_Exit;
 
 using ::labs;
 using ::llabs;
+#ifdef __SIZEOF_INT48__
+using ::i48abs;
+#endif // __SIZEOF_INT48__
 
 using ::div;
 using ::ldiv;