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      1 /* Symbol concatenation utilities.
      2 
      3    Copyright (C) 1998-2016 Free Software Foundation, Inc.
      4 
      5    This program is free software; you can redistribute it and/or modify
      6    it under the terms of the GNU General Public License as published by
      7    the Free Software Foundation; either version 2 of the License, or
      8    (at your option) any later version.
      9 
     10    This program is distributed in the hope that it will be useful,
     11    but WITHOUT ANY WARRANTY; without even the implied warranty of
     12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     13    GNU General Public License for more details.
     14 
     15    You should have received a copy of the GNU General Public License along
     16    with this program; if not, write to the Free Software Foundation, Inc.,
     17    51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.  */
     18 
     19 #ifndef SYM_CAT_H
     20 #define SYM_CAT_H
     21 
     22 #if defined (__STDC__) || defined (ALMOST_STDC) || defined (HAVE_STRINGIZE)
     23 #define CONCAT2(a,b)	 a##b
     24 #define CONCAT3(a,b,c)	 a##b##c
     25 #define CONCAT4(a,b,c,d) a##b##c##d
     26 #define CONCAT5(a,b,c,d,e) a##b##c##d##e
     27 #define CONCAT6(a,b,c,d,e,f) a##b##c##d##e##f
     28 #define STRINGX(s) #s
     29 #else
     30 /* Note one should never pass extra whitespace to the CONCATn macros,
     31    e.g. CONCAT2(foo, bar) because traditonal C will keep the space between
     32    the two labels instead of concatenating them.  Instead, make sure to
     33    write CONCAT2(foo,bar).  */
     34 #define CONCAT2(a,b)	 a/**/b
     35 #define CONCAT3(a,b,c)	 a/**/b/**/c
     36 #define CONCAT4(a,b,c,d) a/**/b/**/c/**/d
     37 #define CONCAT5(a,b,c,d,e) a/**/b/**/c/**/d/**/e
     38 #define CONCAT6(a,b,c,d,e,f) a/**/b/**/c/**/d/**/e/**/f
     39 #define STRINGX(s) "s"
     40 #endif
     41 
     42 #define XCONCAT2(a,b)     CONCAT2(a,b)
     43 #define XCONCAT3(a,b,c)   CONCAT3(a,b,c)
     44 #define XCONCAT4(a,b,c,d) CONCAT4(a,b,c,d)
     45 #define XCONCAT5(a,b,c,d,e) CONCAT5(a,b,c,d,e)
     46 #define XCONCAT6(a,b,c,d,e,f) CONCAT6(a,b,c,d,e,f)
     47 
     48 /* Note the layer of indirection here is typically used to allow
     49    stringification of the expansion of macros.  I.e. "#define foo
     50    bar", "XSTRING(foo)", to yield "bar".  Be aware that this only
     51    works for __STDC__, not for traditional C which will still resolve
     52    to "foo".  */
     53 #define XSTRING(s) STRINGX(s)
     54 
     55 #endif /* SYM_CAT_H */
     56