Pragma directive syntax

XL C/C++ supports three forms of pragma directives:

#pragma options option_name

These pragmas use exactly the same syntax as their command-line option equivalent. The exact syntax and list of supported pragmas of this type are provided in #pragma options.

#pragma name

This form uses the following syntax:

              .------------------------.   
              V                        |   
>>-#--pragma----name--(--suboptions--)-+-----------------------><

The name is the pragma directive name, and the suboptions are any required or optional suboptions that can be specified for the pragma, where applicable.

_Pragma ("name")

This form uses the following syntax:

                  .------------------------.         
                  V                        |         
>>-_Pragma--(--"----name--(--suboptions--)-+--"--)-------------><

For example, the statement:

_Pragma ( "pack(1)" ) 

is equivalent to:

#pragma pack(1)

For all forms of pragma statements, you can specify more than one name and suboptions in a single #pragma statement.

If you have any pragmas that are not common to both C and C++ in code that will be compiled by both compilers, you may add conditional compilation directives around the pragmas. (This is not strictly necessary since unrecognized pragmas are ignored.) For example, #pragma object_model is only recognized by the C++ compiler, so you may decide to add conditional compilation directives around the pragma.

#ifdef __cplusplus
#pragma object_model(pop)
#endif