absyntax/absyntax.hh
changeset 572 c353bc67bf91
parent 569 0d1ab9e78574
child 607 be9ba3531afb
equal deleted inserted replaced
571:97b85630e496 572:c353bc67bf91
    51 #include <string>
    51 #include <string>
    52 #include <stdint.h>  // required for uint64_t, etc...
    52 #include <stdint.h>  // required for uint64_t, etc...
    53 
    53 
    54 
    54 
    55 /* Determine, for the current platform, which data type (float, double or long double) uses 64 bits. */
    55 /* Determine, for the current platform, which data type (float, double or long double) uses 64 bits. */
    56 /* NOTE: we cant use sizeof() in pre-processor directives, so we do it another way... */
    56 /* NOTE: We cant use sizeof() in pre-processor directives, so we have to do it another way... */
       
    57 /* CURIOSITY: We can use sizeof() and offsetof() inside static_assert() but:
       
    58  *          - this only allows us to make assertions, and not #define new macros
       
    59  *          - is only available in the C standard [ISO/IEC 9899:2011] and the C++ 0X draft standard [Becker 2008]. It is not available in C99.
       
    60  *          https://www.securecoding.cert.org/confluence/display/seccode/DCL03-C.+Use+a+static+assertion+to+test+the+value+of+a+constant+expression
       
    61  *         struct {int a, b, c, d} header_t;
       
    62  *  e.g.:  static_assert(offsetof(struct header_t, c) == 8, "Compile time error message.");
       
    63  */
       
    64 
    57 #include <float.h>
    65 #include <float.h>
    58 #if    (LDBL_MANT_DIG == 53) /* NOTE: 64 bit IEC559 real has 53 bits for mantissa! */
    66 #if    (LDBL_MANT_DIG == 53) /* NOTE: 64 bit IEC559 real has 53 bits for mantissa! */
    59   #define long_double long double
    67   #define long_double long double
    60   #define real64_t long_double /* so we can later use #if (real64_t == long_double) directives in the code! */
    68   #define real64_t long_double /* so we can later use #if (real64_t == long_double) directives in the code! */
    61 #elif  ( DBL_MANT_DIG == 53) /* NOTE: 64 bit IEC559 real has 53 bits for mantissa! */
    69 #elif  ( DBL_MANT_DIG == 53) /* NOTE: 64 bit IEC559 real has 53 bits for mantissa! */