gcc/testsuite/gcc.dg/cpp/spacing1.c

/* Copyright (C) 2000, 2001, 2003 Free Software Foundation, Inc.  */

/* { dg-do preprocess } */
/* { dg-options "-P" } */

/* This tests correct spacing of macro expansion output, as well as
   the line it falls on.  This is quite subtle; it involves newlines
   within macro arguments becoming spaces, but not if it turns out to
   not be a macro invocation.  Also, multiple macro invocations spread
   across many lines.

   Neil Booth, 1 Dec 2000, 23 Sep 2001.  */

/* The actual location of the expansion of a multi-line macro
   invocation is not defined: we might consider them to be in the same
   line as the initial token of the invocation, or as the final token
   of the invocation, or even anything in between.  We choose to make
   it the initial token, such that everything that is in a logical
   line ends up in a single line after preprocessing.

   Alexandre Oliva, Sept 13, 2003.  */

#define str(x) #x
#define f(x) x
#define glue(x, y) x ## y
#define EMPTY
/* These are based on PR 4492, we mustn't lose padding tokens when
   scanning ahead for a '(' and failing to find it.  */
#define A(x) B x
#define B(x)
#define C A
#define D() A

/* The correct output is shown here.  Note the spaces, and the way
   everything after the invocation of f appears on the same line.

 44 ;
B Q B Q A Q A:
f
bar
A
bad
g "1 2" bam baz

*/

glue (EMPTY 4, 4) EMPTY;
A(Q) C(Q) D()Q D():
f
bar
A
bad
f (g) str
(
1
2
) f
(bam) baz

/* { dg-final { scan-file spacing1.i " 44 ;" } }
   { dg-final { scan-file spacing1.i "B Q B Q A Q A:" } }
   { dg-final { scan-file-not spacing1.i "f\[^\n\]*bar" } }
   { dg-final { scan-file spacing1.i "(^|\n)bar" } }
   { dg-final { scan-file spacing1.i "(^|\n)A($|\n)" } }
   { dg-final { scan-file spacing1.i "(^|\n)bad($|\n)" } }
   { dg-final { scan-file spacing1.i "g \"1 2\" bam baz" } } */