COBOL 6.4 user-defined functions - compile dies with 0C1

Pardon the basic question. Infra rolled out COBOL 6.4 last month and I am trying the user-defined function samples from the IBM docs. My understanding was: write the function in one compilation unit, main program in another, call it like a subprogram but with FUNCTION syntax.

Compilation itself is failing. Compiler does not seem to recognize FUNCTION at all and we get a 0C1 during compile step. Docs look clear on paper. Anyone actually got UDF working in a real shop? Is there a PTF or compiler option we missed?

Check you are on the right compiler maintenance and that FUNCTION ALL INTRINSIC is not fighting your UDF setup. Also confirm the function source is in a separate compile with the right repository paragraph. IBM has a few sample JCLs that use IGYWCL with an explicit entry point.

Update: open ticket with IBM. Turns out our compile proc was still pointing at an older SYSLIB chain. Fixed that and the sample compiles. Still working through linkage on our own function.

Good to know it was not just me. Same confusion reading the manual.