Zilog Z8F0130 - Manual (Page 550)

Appendix E. Compatibility Issues UM013037-1212
526
Zilog Developer Studio II – Z8 Encore!
User Manual
updated and in all circumstances. They continue to be supported as they have been in older
releases and will be accepted by the compiler.
Compiler options can be set in the Project Settings dialog box (on the C pages) or by
using the #pragma directives described in this section.
If the #pragma directive is inserted in your code, it overrides the selections you made in
the Project Settings dialog box.
#pragma alias
Enables alias checking. The compiler assumes that program variables can be aliased. This
pragma is the default.
#pragma noalias
Disables alias checking. Before using this pragma, be sure that the program does not use
aliases, either directly or indirectly. An alias occurs when two variables can reference the
same memory location. The following example illustrates an alias:
func()

{

int x,*p;

p = &x; /* both “x” and “*p” refer to same location */

.

.

.

}
If both *p and x are used below the assignment, then malignant aliases exist and the
NOALIAS switch must not be used. Otherwise, alias is benign, and the NOALIAS switch
can be used.
#pragma cpu
Defines the target processor to the compiler.
#pragma globalcopy
Enables global copy propagation.
#pragma noglobalcopy
Disables global copy propagation.
#pragma globalcse
Enables global common elimination unless local common subexpressions are disabled.