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Q63959: Using Unary "+" in QuickC Gives Incorrect Results

Article: Q63959
Product(s): See article
Version(s): 2.50
Operating System(s): MS-DOS
Keyword(s): ENDUSER | s_quickasm buglist2.50 plus | mspl13_c
Last Modified: 25-JUL-1990

The ANSI C standard now defines the unary + operator. However, using
this operator on a float or double precision float data type in QuickC
version 2.50 gives inaccurate results. The following code will
reproduce these results:

/* This code will print out an inaccurate value for
 * variable t
 */

static double t = +.5, tt = .5;

void main(void)
{
        printf("t = %lg tt = %lg\n", t, tt);
}

The output from this program is as follows:

   t = 0 tt = 0.5

This behavior occurs only when using floating point numbers or
doubles. Integers behave as expected.

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