Glen: I vaguely remember in FORTRAN 4 (MFT 19.6?) that it was a DS and not initialized. This was around 1970ish. Fortran G1 AFAIR did so as well. That had to been around 1978ish . Ed
----- Original Message ----- From: glen herrmannsfeldt <[email protected]> To: [email protected] Cc: Sent: Thursday, October 27, 2011 2:20 PM Subject: Filling in the holes There has been an ongoing discussion on comp.lang.fortran on the initialization of variables, including questions about OS/360 and its compilers. As I understand it, Fortran variables, and DS in assembler, generate holes in the object program (no TXT record for that position), and are filled in either by the linkage editor or program fetch. I believe that early OS/360 versions left whatever happened to be there, either in the linkage editor buffer or, for program fetch, in that memory location. At some time later, possibly for security reasons, this was changed to initialize to zero, or maybe something else (such as X'81'). The actual question is: when was this change made and which programs (compilers, linkage editors, program fetch) were changed? -- glen ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
