# minus-zero.m4 serial 2 dnl Copyright (C) 2010-2015 Free Software Foundation, Inc. dnl This file is free software; the Free Software Foundation dnl gives unlimited permission to copy and/or distribute it, dnl with or without modifications, as long as this notice is preserved. # Macros for floating-point negative zero. # Keep in sync with tests/minus-zero.h! # Expands to code that defines a variable or macro minus_zerof. AC_DEFUN([gl_FLOAT_MINUS_ZERO_CODE], [[ #include /* minus_zerof represents the value -0.0f. */ /* HP cc on HP-UX 10.20 has a bug with the constant expression -0.0f. ICC 10.0 has a bug when optimizing the expression -zero. The expression -FLT_MIN * FLT_MIN does not work when cross-compiling to PowerPC on Mac OS X 10.5. */ #if defined __hpux || defined __sgi || defined __ICC static float compute_minus_zerof (void) { return -FLT_MIN * FLT_MIN; } # define minus_zerof compute_minus_zerof () #else float minus_zerof = -0.0f; #endif ]]) # Expands to code that defines a variable or macro minus_zerod. AC_DEFUN([gl_DOUBLE_MINUS_ZERO_CODE], [[ #include /* minus_zerod represents the value -0.0. */ /* HP cc on HP-UX 10.20 has a bug with the constant expression -0.0. ICC 10.0 has a bug when optimizing the expression -zero. The expression -DBL_MIN * DBL_MIN does not work when cross-compiling to PowerPC on Mac OS X 10.5. */ #if defined __hpux || defined __sgi || defined __ICC static double compute_minus_zerod (void) { return -DBL_MIN * DBL_MIN; } # define minus_zerod compute_minus_zerod () #else double minus_zerod = -0.0; #endif ]]) # Expands to code that defines a variable or macro minus_zerol. AC_DEFUN([gl_LONG_DOUBLE_MINUS_ZERO_CODE], [[ #include #if defined __i386__ && (defined __BEOS__ || defined __OpenBSD__) # undef LDBL_MIN # define LDBL_MIN 3.3621031431120935063E-4932L #endif /* minus_zerol represents the value -0.0L. */ /* HP cc on HP-UX 10.20 has a bug with the constant expression -0.0L. IRIX cc can't put -0.0L into .data, but can compute at runtime. ICC 10.0 has a bug when optimizing the expression -zero. The expression -LDBL_MIN * LDBL_MIN does not work when cross-compiling to PowerPC on Mac OS X 10.5. */ #if defined __hpux || defined __sgi || defined __ICC static long double compute_minus_zerol (void) { return -LDBL_MIN * LDBL_MIN; } # define minus_zerol compute_minus_zerol () #else long double minus_zerol = -0.0L; #endif ]])