Conference notes for 2026 04 07

Lmod Zoom Meeting April 7th

Attendees

• Robert McLay
• Chris Ramos
• Taylor Ishisaka
• Jes Persinger
• Kurt Lust
• Shelly Johnson
• Kenneth Hoste
• Lev Gorenstein

Agenda

• Q/A
  • no questions initially
• Lua 5.5 newly released in December 2025
  • Major change: for loop variables now readonly
  • Fedora Rawhide now uses Lua 5.5
  • Issue #807: Request for Lmod to support Lua 5.5
    • Problem: luaposix has not been ported to Lua 5.5
    • However Rawhide has patched luaposix to support 5.5
  • PR #810 and PR #811 tried to patch Lmod that are almost correct
    • Both patches do not support if block scope rules:

      function main()
        local foo = 1
        if (foo == 1) then
          local foo = 4
          local bar = 2
        end
        print("foo: ",foo)
        print("bar: ",bar)
      end
      main()
      
      foo is 1
      bar is nil

    • For example: An incorrect patch

      for k, v in pairs(newT) do
          if (v == false) then local v = nil end
          setenv_posix(k,v, true)
      end

    • Where as I have:

      for k, myValue in pairs(newT) do
          local v = myValue
          if (v == false) then v = nil end
          setenv_posix(k,v, true)
      end

    • Upshot: Robert got to relearn how to build and use containers
    • Also expanded rawhide's luaposix src.rpm to extract a luaposix that works for Lua 5.5
• Xavier Delaruelle presented an Lmod status talk at HPSF'26
  • His only question was about how Lmod reduced the amount of records to optional Lmod DB
  • Solution: Remove de-dup records from same user, same day.
  • Part 2: New DB schema: Only one table, Keep only a year's worth of data
• Lmod 9.2 Released with Lua 5.5 support.
  • Lmod 9.2 works with all Lua 5.* version.
  • Luaposix that works with Lua 5.5 currently only available on Fedora Rawhide.
• Robert will be presenting at Easy Build User Meeting (EUM '26) in Portugal (April 21 - 23)
  • see https://easybuild.io/eum26
  • Lmod talk will be on Wed 22 April at 16:15-16:45 WEST (same as UK time)

Next Meeting 5 May 2026