C/C++ Programmer's Guide (G06.27+, H06.08+, J06.03+)

20
invalid constant expression
Cause
The compiler encountered an expression that did not evaluate to a constant in a context that
required a constant result. This error can occur if one of the operators not valid for constant
expressions was present.
21
illegal use of aggregate
Cause
An identifier declared as a structure or union was encountered in an expression without being
properly qualified by an aggregate reference.
22
structure used as function argument
Cause
An identifier declared as a structure or union appeared as a function argument without the
preceding address-of operator. Although you can pass a structure by value, this warning reminds
you that it is inefficient to do so.
23
invalid use of conditional operator
Cause
You used the conditional operator erroneously. This error can occur if the question mark was
present but the colon was not found when expected.
24
pointer operand required
Cause
The context of the expression required a pointer operand. This error can occur if the expression
following the * indirection operator did not evaluate to a pointer.
25
lvalue required
Cause
The context of the expression required an operand to be an lvalue. This error can occur if the
expression following the address-of operator was not an lvalue, or if the left side of an assignment
expression was not an lvalue.
26
arithmetic operand required
Cause
The context of the expression required an operand to be arithmetic (not a pointer, function, or
aggregate).
27
arithmetic or pointer operand required
332 TNS C Compiler Messages