include/gsl/gsl_inline.h

0001 /* gsl_inline.h
0002  *
0003  * Copyright (C) 2008, 2009 Brian Gough
0004  *
0005  * This program is free software; you can redistribute it and/or modify
0006  * it under the terms of the GNU General Public License as published by
0007  * the Free Software Foundation; either version 3 of the License, or (at
0008  * your option) any later version.
0009  *
0010  * This program is distributed in the hope that it will be useful, but
0011  * WITHOUT ANY WARRANTY; without even the implied warranty of
0012  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
0013  * General Public License for more details.
0014  *
0015  * You should have received a copy of the GNU General Public License
0016  * along with this program; if not, write to the Free Software
0017  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
0018  */
0019
0020 #ifndef __GSL_INLINE_H__
0021 #define __GSL_INLINE_H__
0022
0023 /* In recent versiions of GCC, the inline keyword has two different
0024    forms: GNU and C99.
0025
0026    In GNU mode we can use 'extern inline' to make inline functions
0027    work like macros.  The function is only inlined--it is never output
0028    as a definition in an object file.
0029
0030    In the new C99 mode 'extern inline' has a different meaning--it
0031    causes the definition of the function to be output in each object
0032    file where it is used.  This will result in multiple-definition
0033    errors on linking.  The 'inline' keyword on its own (without
0034    extern) has the same behavior as the original GNU 'extern inline'.
0035
0036    The C99 style is the default with -std=c99 in GCC 4.3.
0037
0038    This header file allows either form of inline to be used by
0039    redefining the macros INLINE_DECL and INLINE_FUN.  These are used
0040    in the public header files as
0041
0042         INLINE_DECL double gsl_foo (double x);
0043         #ifdef HAVE_INLINE
0044         INLINE_FUN double gsl_foo (double x) { return x+1.0; } ;
0045         #endif
0046
0047 */
0048
0049 #ifdef HAVE_INLINE
0050 #  if defined(__GNUC_STDC_INLINE__) || defined(GSL_C99_INLINE) || defined(HAVE_C99_INLINE)
0051 #    define INLINE_DECL inline  /* use C99 inline */
0052 #    define INLINE_FUN inline
0053 #  else
0054 #    define INLINE_DECL         /* use GNU extern inline */
0055 #    define INLINE_FUN extern inline
0056 #  endif
0057 #else
0058 #  define INLINE_DECL /* */
0059 #endif
0060
0061 /* Range checking conditions in headers do not require any run-time
0062    tests of the global variable gsl_check_range.  They are enabled or
0063    disabled in user code at compile time with GSL_RANGE_CHECK macro.
0064    See also build.h. */
0065 #define GSL_RANGE_COND(x) (x)
0066
0067 #endif /* __GSL_INLINE_H__ */