Q59539: ICE Error When Casting Pointer Arithmetic Result

Article: Q59539
Product(s): See article
Version(s): 2.00 2.01
Operating System(s): MS-DOS
Keyword(s): ENDUSER | buglist2.00 buglist2.01 | mspl13_c
Last Modified: 29-MAY-1990

When casting the result of pointer arithmetic to either a double or a
float, QuickC Version 2.00 or QuickAssembler Version 2.01 may produce
the following internal compiler error when compiling in small, medium,
compact, or large models:

   ice.c(7) : fatal error C1001: Internal Compiler Error
         (compiler file 'gencode.c', line 389)
         Contact Microsoft Technical Support

Turning off all optimizations by use of the /Od switch does not help.

Sample Code
-----------

void main(void)
{
   char * foo = "abcdef",
        * bar = foo + 5 ;
   double dbl;

   dbl = (double) (foo-bar) ;
}

Substituting "float" for "double" produces the same error.

The problem can be solved by using a temporary variable of type int to
store the result of the pointer arithmetic. Type int is used because
in all models (except huge), pointer arithmetic is done in 2-byte
signed (that is, int) arithmetic.

The following is the same as the above example, but uses a temporary
variable to store the result of the pointer arithmetic.

void main(void)
{
   char * foo = "abcdef",
        * bar = foo + 5 ;
   double dbl ;
   int    temp ;

   temp = foo-bar ;
   dbl  = (double) temp ;
}

Microsoft has confirmed this to be a problem with QuickC Versions 2.00
and 2.01. We are researching this problem and will post new
information here as it becomes available.

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