Hardware upward compatibility of problem state code is darned near 100%. Some privileged instructions have gone away, but that is only a concern if you are porting an OS, or OS-like code such as "extreme" system exits.
Software compatibility is 98 or 99%. For example, application code that assumes certain 24-bit MVS fields could be used directly as addresses will fail on modern z/OS. Charles -----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of Grant Steele Sent: Sunday, March 29, 2020 3:40 PM To: [email protected] Subject: Upwards Compatibility of Code in Z series Boxes Impressed with the depth on this list from the contributors. I am getting back into the z-series software and application development after years of being in another domain. Here is a very broad question: when you guys/girls are moving your app portfolio from one hardware platform to another (say, z14 to z15), to what extend are the apps compatible with the new platform without recompilation? ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
