libm.h

ecos为实时嵌入式操作系统

                          this will best help code size and speed, as well
                          as omitting the code for other compatibility
                          modes. If not defined, the math library can be
                          set at run-time to any of the supported
                          compatibility modes."
            type         radio
            parent       CYGPKG_LIBM_COMPATIBILITY
        }

        cdl_component CYGPKG_LIBM_COMPATIBILITY_DEFAULT {
            display      "Default mode"
            description  "If you want to have support for more than one
                          compatibility mode settable at run-time, rather
                          than hard-coded IEEE mode, this component lets
                          you choose which mode should be the default."
            type         radio
            parent       CYGPKG_LIBM_COMPATIBILITY
            requires     CYGPKG_LIBC
        }
        
        cdl_option CYGNUM_LIBM_COMPATIBILITY_POSIX {
            display      "POSIX"
            description  "This sets the default compatibility mode to
                          POSIX"
            type         radio
            parent       CYGPKG_LIBM_COMPATIBILITY_DEFAULT
        }

        cdl_option CYGNUM_LIBM_COMPATIBILITY_IEEE {
            display      "IEEE"
            description  "This sets the default compatibility mode to IEEE"
            type         radio
            parent       CYGPKG_LIBM_COMPATIBILITY_DEFAULT
        }

        cdl_option CYGNUM_LIBM_COMPATIBILITY_XOPEN {
            display      "X/OPEN"
            description  "This sets the default compatibility mode to
                          X/OPEN"
            type         radio
            parent       CYGPKG_LIBM_COMPATIBILITY_DEFAULT
        }

        cdl_option CYGNUM_LIBM_COMPATIBILITY_SVID {
            display      "SVID"
            description  "This sets the default compatibility mode to SVID"
            type         radio
            parent       CYGPKG_LIBM_COMPATIBILITY_DEFAULT
        }

        cdl_option CYGFUN_LIBM_SVID3_scalb {
            display      "SVID3-style scalb()"
            description  "SVID3 defined the scalb() function as double
                          scalb(double, double) rather than double
                          scalb(double, int) which is used by IBM, DEC, and
                          probably others. Enabling this option chooses
                          the (double, double) version. Note there is a
                          function double scalbn(double, int) which is
                          unaffected by this choice."
            type         boolean
            parent       CYGPKG_LIBM_COMPATIBILITY
        }
        
        cdl_option CYGSYM_LIBM_NO_XOPEN_SVID_NAMESPACE_POLLUTION {
            display      "Reduce namespace pollution"
            description  "If you do not want to use either the X/Open or
                          SVID3 compatibility modes, you may want to define
                          this option to reduce the chance of namespace
                          pollution. This is particularly likely to occur
                          here as these standards define symbols with
                          names that often appear in applications, such as
                          exception, DOMAIN, OVERFLOW, etc. If your
                          application also used these names, it may cause
                          problems."
            type         boolean
            parent       CYGPKG_LIBM_COMPATIBILITY
        }

        cdl_option CYGSEM_LIBM_USE_STDERR {
            display      "Output to stderr for math errors"
            description  "The SVID3 standard says that error
                          messages should be output on the stderr console
                          output stream. This option allows this ability
                          to be explicitly controlled. However, this still
                          only has an effect in SVID3 compatibility mode."
            type         boolean
            requires     !CYGSEM_LIBM_COMPAT_IEEE_ONLY
            requires     CYGPKG_LIBC_STDIO
            parent       CYGPKG_LIBM_COMPATIBILITY
        }

    }}CFG_DATA
*/

#undef CYGSEM_LIBM_COMPAT_IEEE_ONLY
#define CYGPKG_LIBM_COMPATIBILITY_DEFAULT

#ifdef CYGPKG_LIBM_COMPATIBILITY_DEFAULT
# ifndef CYGPKG_LIBC
#  error You must include the libc package if enabling \
 CYGPKG_LIBM_COMPATIBILITY_DEFAULT
# endif
#endif

#define CYGNUM_LIBM_COMPATIBILITY_POSIX
#undef CYGNUM_LIBM_COMPATIBILITY_IEEE
#undef CYGNUM_LIBM_COMPATIBILITY_XOPEN
#undef CYGNUM_LIBM_COMPATIBILITY_SVID


#if defined(CYGPKG_LIBM_COMPATIBILITY_DEFAULT)
# if defined(CYGNUM_LIBM_COMPATIBILITY_POSIX)
#  define CYGNUM_LIBM_COMPAT_DEFAULT CYGNUM_LIBM_COMPAT_POSIX
# elif defined(CYGNUM_LIBM_COMPATIBILITY_IEEE)
#  define CYGNUM_LIBM_COMPAT_DEFAULT CYGNUM_LIBM_COMPAT_IEEE
# elif defined(CYGNUM_LIBM_COMPATIBILITY_XOPEN)
#  define CYGNUM_LIBM_COMPAT_DEFAULT CYGNUM_LIBM_COMPAT_XOPEN
# elif defined(CYGNUM_LIBM_COMPATIBILITY_SVID)
#  define CYGNUM_LIBM_COMPAT_DEFAULT CYGNUM_LIBM_COMPAT_SVID
# else
#  error Configuration broken - no default mode set
# endif
#endif

#define CYGFUN_LIBM_SVID3_scalb

#undef CYGSYM_LIBM_NO_XOPEN_SVID_NAMESPACE_POLLUTION

#undef CYGSEM_LIBM_USE_STDERR

//========================================================================
//
// THREAD-SAFETY CONFIGURATION OPTIONS

/*
    {{CFG_DATA

        cdl_component CYGPKG_LIBM_THREAD_SAFETY {
            display      "Thread safety"
            description  "This option controls whether the C library has
                          support for thread safe operation in general.
                          This requires eCos kernel support for per-thread
                          data, and adjustment of the stack limit."
            type          dummy
            parent        CYGPKG_LIBM
            doc           ref/ecos-ref/c-and-math-library-overview-thread-safety.html
        }

        cdl_option CYGSEM_LIBM_THREAD_SAFE_COMPAT_MODE {
            display      "Compatibility mode setting"
            description  "This option makes the setting of the compatiblity
                          mode be a per-thread property. This directly
                          implies that it also becomes thread-safe."
            requires     !CYGSEM_LIBM_COMPAT_IEEE_ONLY
            requires     CYGVAR_KERNEL_THREADS_DATA
            parent       CYGPKG_LIBM_THREAD_SAFETY
        }
    }}CFG_DATA

*/


#ifndef CYGSEM_LIBM_COMPAT_IEEE_ONLY // irrelevant if mode is constant
#undef CYGSEM_LIBM_THREAD_SAFE_COMPAT_MODE
#endif


#if ( defined(CYGSEM_LIBM_THREAD_SAFE_COMPAT_MODE) && \
      !defined(CYGVAR_KERNEL_THREADS_DATA) )
# error The kernel must have thread-specific data \
  (CYGVAR_KERNEL_THREADS_DATA) turned on for a thread-safe math library
#endif

//========================================================================
//
// TRACING OPTIONS

/*
    {{CFG_DATA

        cdl_component CYGPKG_LIBM_TRACE {
            display      "Tracing output levels in Math library"
            description  "Tracing support is useful for debugging. Some
                          Math library modules can be configured with
                          different levels of tracing verbosity. These
                          levels can be configured here."
            type         boolean
            requires     CYGDBG_USE_TRACING
            parent       CYGPKG_LIBM
        }

        cdl_option CYGNUM_LIBM_COMPATMODE_TRACE_LEVEL {
            display      "Compatibility mode get/set"
            description  "Trace level for debugging the getting and
                          setting of the compatibility mode when it is
                          configured to be thread-safe."
            type         count
            legal_values 0 to 1
            requires     CYGSEM_LIBM_THREAD_SAFE_COMPAT_MODE
            parent       CYGPKG_LIBM_TRACE
        }
    }}CFG_DATA

*/

#undef CYGPKG_LIBM_TRACE

#ifdef CYGPKG_LIBM_TRACE

#define CYGNUM_LIBM_COMPATMODE_TRACE_LEVEL 0


#endif


#endif // CYGONCE_PKGCONF_LIBM_H multiple inclusion protection

// EOF libm.h