/*

 *  undefs.c:

 * 1998/08          made public                                 kmatsui

 * 2002/12          slightly revised                            kmatsui

 * 2003/11          slightly revised                            kmatsui

 *

 *   Each of the following texts causes undefined behavior.  Good pre-

 * processor will diagnose or warn at these texts, or at least document the

 * behavior on these cases.

 */

#include    <stdio.h>

#define str( a)     # a

main( void)

{

    int     a = 1, b = 2;

    char *  string;

/* u.1.1:   End of a source file without <newline>. */

#include    "unbal3.h"

int e_1;

/* u.1.2:   End of a source file with <backslash><newline>. */

#include    "unbal4.h"

;

/* u.1.3:   End of a source file with an unterminated comment.  */

#include    "unbal5.h"

*/

/* u.1.4:   End of a source file with an uncompleted macro call.    */

#include    "unbal6.h"

    y);

/* u.1.5:   Illegal characters (in other than string literal, character

        constant, header-name or comment).  */

#if     1 ||?2?

/*    0x01e ^ ^ 0x1f    */

#endif  /* Maybe the second error.  */

/* u.1.6:   [VT], [FF] in directive line.   */

#if     1 ||?2

/*     [VT] ^ ^ [FF]    */

#endif  /* Maybe the second error.  */

/* u.1.7:   Invalid multi-byte character sequence (in string literal,

        character constant, header-name or comment).    */

#if     'Ž== 0x8e

/*       ^ 0x8e */

#endif  /* Maybe the second error.  */

/* u.1.8:   Unterminated character constant.    */

/*  The following "comment" may not interpreted as a comment but swallowed by

        the unterminated character constant.    */

#error  I can't understand. /* Token error prior to execution of #error.    */

/* u.1.9:   Unterminated string literal.    */

    string =

    "String literal

    across the lines.

"

;

/* u.1.10:  Unterminated header-name.   */

#include    

/* u.1.11:  Header-name containing ', ", \ or "/*". */

/*  Probably illegal filename and fails to open.    */

#include    "../*line.h"

/*  \ is a legal path-delimiter in MS-DOS or some other OS's.   */

#include    "..\test-c\line.h"

/* u.1.12:  Argument of #include other than header-name.    */

#include    filename

/* u.1.13:  Excessive argument in #include directive.   */

#include    <assert.h>  Junk

/* u.1.14:  #line directive without an argument of line number. */

#line   "filename"

/* u.1.15:  #line directive with the second argument of other than string

        literal.    */

#line   1234    filename

/* u.1.16:  Excessive argument in #line directive.  */

#line   2345    "filename"  Junk

/*  90, undefs.c or other undefined results.    */

    printf( "%d, %s\n", __LINE__, __FILE__);

/* u.1.17:  Line number argument of #line directive should be in range of

        [1,32767].  */

#line   32767   /* valid here   */

/* line 32767   */

/* line 32768 ? : out of range  */

    printf( "%d\n", __LINE__);

                    /* 32769 ? or -32767 ?, maybe warned as an out-of-range */

#line   0

#line   32768

/* u.1.18:  Line number argument of #line directive should be written in

        decimal digits. */

#line   0x1000

#line   108     /* Restore to correct line number.  */

/* u.1.19:  A macro expanded to "defined" in #if expression.    */

#define DEFINED     defined

#if     DEFINED DEFINED

#endif

#undef  __linux__

#undef  __arm__

#define __linux__   1

#define HAVE_MREMAP defined(__linux__) && !defined(__arm__)

/* Wrong macro definition.

 * This macro should be defined as follows.

 *  #if defined(__linux__) && !defined(__arm__)

 *  #define HAVE_MREMAP 1

 *  #endif

 */

#if HAVE_MREMAP

    mremap();

#endif

/* u.1.20:  Undefining __FILE__, __LINE__, __DATE__, __TIME__, __STDC__,

        __STDC_VERSION__ or "defined" in #undef directive.  */

#undef  __LINE__

/*  131 or other undefined result.  */

    printf( "%d\n", __LINE__);

/* u.1.21:  Defining __FILE__, __LINE__, __DATE__, __TIME__, __STDC__,

        __STDC_VERSION__ or "defined" in #define directive. */

#define __LINE__    1234

/*  137 or other undefined result.  */

    printf( "%d\n", __LINE__);

#define defined     defined

#if     defined defined

#   error   I am not a good preprocessor.

#endif

/* u.1.22:  Result of ## operator is not a valid pp-token.  */

#define NUM( dig, exp)  dig ## E+ ## exp

/*

 *   "E+" is a sequence of two pp-tokens "E" and "+", not a single pp-token.

 * The first ## concatenates the last pp-token of first argument with "E",

 * and the second ## concatenates "+" with the first pp-token of the second

 * argument.

 *   While "12E" (one of the sequence generated by the token concatenation)

 * is a valid pp-token, "+34" (the another sequence) is not a valid pp-token

 * and causes an undefined behavior.

 */

    printf( "%e\n", NUM( 12, 34));

/* u.1.23:  Result of # operator is not a valid string literal. */

/*  "\\"\"";    This sequence is parsed to three tokens "\\" \ "", and will be

        diagnosed by compiler-proper unless diagnosed by preprocessor.  */

    puts( str( \""));

/* u.1.24:  Empty argument of macro call.   */

/*

 *   Note: Since no argument and one empty argument cannot be distinguished

 * syntactically, additional dummy argument may be necessary for an

 * intermediate macro to process one empty argument (if possible).

 */

#define ARG( a, dummy)      # a

#define EMPTY

#define SHOWN( n)       printf( "%s : %d\n", # n, n)

#define SHOWS( s)       printf( "%s : %s\n", # s, ARG( s, dummy))

#define add( a, b)      (a + b)

#define sub( a, b)      (a - b)

#define math( op, a, b)     op( a, b)

#define APPEND( a, b)       a ## b

/*  printf( "%s : %d\n", "math( sub, , y)", ( - y));

        or other undefined behavior.    */

    SHOWN( math( sub, , y));

/*  printf( "%s : %s\n", "EMPTY", "");

        or other undefined behavior.    */

    SHOWS( EMPTY);

/*  printf( "%s : %s\n", "APPEND( CON, 1)", "CON1");    */

    SHOWS( APPEND( CON, 1));

/*  printf( "%s : %s\n", "APPEND( CON, )", "CON");

        or other undefined behavior.    */

    SHOWS( APPEND( CON, ));

/*  printf( "%s : %s\n", "APPEND( , )", "");

        or other undefined behavior.    */

    SHOWS( APPEND( , ));

/* u.1.25:  Macro argument otherwise parsed as a directive. */

/*  "#define NAME"; or other undefined behaviour.   */

    puts( str(

#define NAME

    ));

#define sub( x, y)      (x - y)

#define SUB             sub

#if 0   /* Added by C90: Corrigendum 1 (1994) and deleted by C99    */

/* u.1.26:  Expanded macro replacement list end with name of function-like

        macro.  */

    SUB( a, b);

#endif

/* u.1.27:  Unknown preprocessing directive (other than #pragma).   */

#ifdefined MACRO

#endif              /* The second error.    */

#define D   define

/* u.1.28:  There are following two ways of preprocessing.

    1:  "D" isn't expanded, because # is the first token of the line.

        Preprocessor reports that "D" is an unknown directive.

    2:  "D" is expanded, because that is not a directive.

        Compiler-phase will diagnose the output of preprocess.

    Anyway, preprocessor should not interprete this line as a preprocessing

    directive.

 */

#D  A   B

/* u.2.1:   Undefined escape sequence.  */

#if     '\x'

#endif

/* u.2.2:   Illegal bit shift count.    */

#if     1 << -1

#endif

#if     1 << 64

#endif

    return  0;

}