User`s guide

Preparing to Port Macro-32 Code

This chapter describes a process that software engineers can use when planning

to port Macro-32 code from an OpenVMS VAX system to an OpenVMS Alpha or

HP OpenVMS Industry Standard 64 system.

This chapter contains the following topics:

• Section 1.1, Features of the MACRO Compiler

• Section 1.2, Differences Between the Compiler and the Assembler

• Section 1.3, Step-by-Step Porting Process for OpenVMS VAX to OpenVMS

Alpha or OpenVMS I64

• Section 1.4, Step-by-Step Porting Process for OpenVMS Alpha to OpenVMS

I64

• Section 1.5, Identifying Nonportable VAX MACRO Coding Practices

• Section 1.6, Establishing Useful Coding Conventions

• Section 1.7, Maintaining Common Sources

Note

See Appendix A for information on how to invoke the compiler.

1.1 Features of the MACRO Compiler

The OpenVMS MACRO compiler compiles Macro-32 source code written for

OpenVMS VAX systems (the VAX MACRO assembler) into machine code that

runs on OpenVMS Alpha and OpenVMS I64 systems.

Note

This compiler is provided for porting Macro-32 code to OpenVMS Alpha

and OpenVMS I64 systems. For any new development, it is recommended

that you use mid- and high-level languages.

While some VAX MACRO code can be compiled without any changes, most

code modules will require the addition of entry point directives when ported

to OpenVMS Alpha or OpenVMS I64. Many code modules will require other

changes as well.

The compiler might detect only a few problems with a module at its initial

compilation and then, after you have corrected them, the compiler might discover

additional problems. In such cases, the resolution of one problem can allow the

Preparing to Port Macro-32 Code 1–1