Windows findlib.conf path variable breaks. Needs a semicolon instead of colon as a path separator

[jesse-greathouse]

On Windows 11

I'm not executing under Cygwin or WSL, this is just on plain Windows in PowerShell.

PS C:\Users\jessegreathouse> opam config report
# opam config report
# opam-version         2.4.1
# self-upgrade         no
# system               arch=x86_64 os=win32 os-distribution=msys2 os-version=10.0.26100
# solver               builtin-mccs+glpk
# install-criteria     -removed,-count[avoid-version,changed],-count[version-lag,request],-count[version-lag,changed],-count[missing-depexts,changed],-changed
# upgrade-criteria     -removed,-count[avoid-version,changed],-count[version-lag,solution],-count[missing-depexts,changed],-new
# jobs                 23
# repositories         1 (http) (default repo at 5b99878077ddf3134c09e188d937954bd33cfa58)
# pinned               1 (git)
# current-switch       5.3.0
# invariant            ["ocaml-base-compiler" {= "5.3.0"}]
# compiler-packages    arch-x86_64.1, conf-mingw-w64-gcc-x86_64.1, flexdll.0.44, msys2.0.1.0, msys2-mingw64.1, ocaml-base-compiler.5.3.0, ocaml-compiler.5.3.0, ocaml-env-mingw64.1, ocaml-options-vanilla.1, system-mingw.1
# msys2:msystem        MINGW64
# msys2:carch          x86_64
# msys2:chost          x86_64-w64-mingw32
# msys2:root           /mingw64
# msys2:native-root    C:\msys64\mingw64
# msys2:package-prefix mingw-w64-x86_64
# ocaml:native         true
# ocaml:native-tools   true
# ocaml:native-dynlink true
# ocaml:stubsdir       C:\Users\jessegreathouse\AppData\Local\opam\5.3.0/lib/ocaml/stublibs;C:\Users\jessegreathouse\AppData\Local\opam\5.3.0/lib/ocaml
# ocaml:preinstalled   false
# ocaml:compiler       5.3.0

The findlib.conf file was generated using ":" (colon) as a path separator instead of ";" (semicolon). With Windows paths this won't work because Windows paths recognize the colon character as part of the path for it's drive letters. (e.g. "C:" , "D:", etc...)

The findlib.conf was originally generated like this:

destdir="C:\\Users\\jessegreathouse\\AppData\\Local\\opam\\5.3.0\\lib"
path="C:\\Users\\jessegreathouse\\AppData\\Local\\opam\\5.3.0/lib/ocaml:C:\\Users\\jessegreathouse\\AppData\\Local\\opam\\5.3.0\\lib"
ocamlc="ocamlc.opt"
ocamlopt="ocamlopt.opt"
ocamldep="ocamldep.opt"
ocamldoc="ocamldoc.opt"

The problem was the colon in the middle of the path= value:

path="C:\\Users\\jessegreathouse\\AppData\\Local\\opam\\5.3.0/lib/ocaml:C:\\Users\\jessegreathouse\\AppData\\Local\\opam\\5.3.0\\lib"

Once I changed it to this (semicolon):

path="C:\\Users\\jessegreathouse\\AppData\\Local\\opam\\5.3.0/lib/ocaml;C:\\Users\\jessegreathouse\\AppData\\Local\\opam\\5.3.0\\lib"

everything was fine.

Difficult to understand how severe or important this is; but I thought I'd mention it in case anyone needed to see this.