XENIX Intermediate Code Incompatibility

Product Version(s): 3.30
Operating System:   XENIX
Flags: enduser |
Last Modified: 22-FEB-1988    ArticleIdent: Q11140

Question:
   Do Microsoft's compilers use the same intermediate code format as
that specified by AT&T? Under System V, AT&T has their own type of
Cmerge project where compilers such as the portable C compiler and the
portable FORTRAN compiler use the same code generator.

Response:
   No, Microsoft's compilers do not use the same intermediate code
format as that specified by AT&T.
   To create the same intermediate code from one compiler to another,
a detailed knowledge of the compiler internals is necessary. This is
possible only if you have written the compiler, or if you have the
source code and access to someone who built it.
   In our case, we have intermediate code compatibility within our own
products, but not relative to AT&T.
   Intermediate code compatibility is not possible because our XENIX
compilers are similar to our DOS compilers, without the DOS trimmings
and instead with some XENIX trimmings. This makes us incompatible with
AT&T, because our DOS compilers were built for intermediate code
compatibility between MS-DOS PASCAL and FORTRAN (PAS2 is the same for
both compilers).
