SOM Compiler

New features, known limitations, and restrictions pertain to the SOM compiler. There are briefly described as follows:

• Mutually recursive IDL struct and union are not currently supported. The following is an example of unsupported mutual recursion:

    struct X;
    struct Y
    {
      sequence<X> indirectSelf;
    };
    struct X
    {
      sequence<Y> indirectSelf;
    };
  

• The C bindings do not permit the use of multiple methods with the same name that also take an argument of data type VA_LIST within the same module. For example, the following legal IDL will result in incorrect C usage bindings:

    module X
    {
      interface Y
      {
        void Foo (in LONG f, in VA_LIST ap);
      };
      interface Z
      {
        void Foo (in LONG f, in VA_LIST ap);
      };
    };
  

• The SOM C++ language bindings are built assuming use of the VisualAge C++ for OS/2 compiler, but other C++ compilers should be able to use these bindings as well. For example, to use BCOS2 (the Borland C++ compiler for OS/2), use -DSOMLINK=_syscall on the compile line, and make sure that the SOMobjects' include directory is consulted before BCOS2/include (because BCOS2/include contains older SOM.H include files).

• If the SOM compiler is interrupted by the user (using Ctrl+C, for example), it sometimes leaves a temporary file with a .CTN extension in the temporary directory specified by the SMTMP environmental variable. These temporary files should be removed periodically.

• When direct references to SOMFOREIGN types are made in an IDL struct or union, the C or C++ language bindings are generated incorrectly. To refer to a SOMFOREIGN type (for example, "somId") in a struct or union , it is necessary to supply a secondary typedef for "somId." For example:

    #include <somobj.idl>
    struct S1
    {
      somId badId;    /* Generates incorrect */
    };                /* C/C++ bindings      */
    #include <somobj.idl>
    typedef somId somId2;
    struct S1
    {
      somId2 badId;   /* OK                  */
    };