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Q47035: QC 2.00: Watch Values on Float Pointers Show char String

Article: Q47035
Product(s): See article
Version(s): 2.00
Operating System(s): MS-DOS
Keyword(s): ENDUSER | buglist2.00 | mspl13_c
Last Modified: 26-JUL-1989

QuickC Version 2.00 does not display float pointers correctly in the
Watch Value window. Float pointers display an ASCII character string
of the memory that it points to, until a null character is reached.

Use the following method as a workaround:

For a float pointer, declared as

   float *fl;

display the pointer in the Watch Value window as

   &*fl : 0xSEG:0xOFF         <---- displays correctly

which essentially says "the address of what fl points to,"
rather than the following

   fl   : "<garbage>"         <---- displays char string

which displays the ASCII string of what fl points to.

The following Watch Value displays the first byte that fl points to as
an ASCII character before program execution begins, but displays the
correct results after initialization:

   *fl  :

Microsoft has confirmed this to be a problem in QuickC Version 2.00.
We are researching this problem and will post new information as it
becomes available.

Example
-------

    float *fl

    fl = (float *) malloc (sizeof(float));
    *fl = 3.5 ;

A Watch Value set to fl displays the following:

    fl : "<garbage>"

The "garbage" is an ASCII character string of the memory that fl
points to. The string continues until a null character is encountered.
The float pointer Watch Value displays a string even before program
execution, when other watch values display <Unknown Identifier>.

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