bug#48444: 28.0.50; package.el wrong path for package-gnupghome-dir on win10

[arthur . miller]

Recipe: start Emacs started -Q flag from mingw64 bash prompt (msys2).

I have freshly installed msys2 + deps + Emacs 28.0.50 from
master. Package installation failes due to some problem with how path for
`package-gnupghome-dir' is interpreted/setuped. Don't know really,
haven't investigated myself. Paths originally evals to:
"c:/Users/arthu/.emacs.d/elpa/gnupg" which is correct, but somehow
Emacs/package.el does not understands it or pass it wrongly to gpg;
since gpg ends up with this path:

/c/Users/arthu/.emacs.d/c:/Users/arthu/.emacs.d/elpa/gnupg/pubring.kbx.

I am pasting the error I get when trying go install a package:

Failed to verify signature archive-contents.sig:
No public key for 066DAFCB81E42C40 created at 2021-05-13T23:10:01+0200 using RSA
Command output:
gpg: keyblock resource 
'/c/Users/arthu/.emacs.d/c:/Users/arthu/.emacs.d/elpa/gnupg/pubring.kbx': No 
such file or directory
gpg: Signature made Thu May 13 23:10:01 2021    
gpg:                using RSA key C433554766D3DDC64221BFAA066DAFCB81E42C40
gpg: Can't check signature: No public key

If I setq path to use Unix prefix '/c/...' instead of 'C:/...' things
seems to work:

(setq package-gnupghome-dir "/c/Users/arthu/.emacs.d/elpa/gnupg")

Not sure if it is Emacs bug or on gpg side, but it is an issue.


Configured using:
 'configure --host=x86_64-w64-mingw32 --target=x86_64-w64-mingw32
 --build=x86_64-w64-mingw32 --with-cairo --without-modules
 --without-compress-install --with-x-toolkit=no --with-gnutls
 --without-gconf --without-xwidgets --without-xaw3d --without-gsettings
 --with-mailutils --with-native-compilation 'CFLAGS=-O3 -mtune=native
 -march=native -fomit-frame-pointer' build_alias=x86_64-w64-mingw32
 host_alias=x86_64-w64-mingw32 target_alias=x86_64-w64-mingw32
 PKG_CONFIG_PATH=/mingw64/lib/pkgconfig:/mingw64/share/pkgconfig'

Configured features:
ACL DBUS GIF GMP GNUTLS HARFBUZZ JPEG JSON LCMS2 LIBXML2 NATIVE_COMP
NOTIFY W32NOTIFY PDUMPER PNG RSVG SOUND THREADS TIFF TOOLKIT_SCROLL_BARS
XPM ZLIB

Important settings:
  value of $LC_CTYPE: sv_SE.UTF-8
  value of $LANG: SVE
  locale-coding-system: cp1252

Major mode: Org

Minor modes in effect:
  org-init-mode: t
  shell-dirtrack-mode: t
  tooltip-mode: t
  global-eldoc-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Load-path shadows:
c:/msys64/mingw64/share/emacs/28.0.50/lisp/transient hides 
c:/Users/arthu/.emacs.d/elpa/transient-20210426.2141/transient
c:/Users/arthu/.emacs.d/lisp/company-cmake hides 
c:/Users/arthu/.emacs.d/elpa/company-20210513.1853/company-cmake
c:/Users/arthu/.emacs.d/lisp/bind-key hides 
c:/Users/arthu/.emacs.d/elpa/bind-key-20160227.48/bind-key

Features:
(shadow sort mail-extr emacsbug sendmail mm-archive gnutls
network-stream url-http url-gw nsm url-cache url-auth finder-inf
helm-easymenu info autoload radix-tree lisp-mnt package url-handlers
org-element avl-tree generator ol-eww eww xdg url-queue thingatpt mm-url
ol-rmail ol-mhe ol-irc ol-info ol-gnus nnselect gnus-search eieio-opt
speedbar ezimage dframe gnus-art mm-uu mml2015 mm-view mml-smime smime
dig gnus-sum shr kinsoku svg dom browse-url url url-proxy url-privacy
url-expand url-methods url-history url-cookie url-domsuf url-util
url-parse url-vars mailcap gnus-group gnus-undo gnus-start gnus-dbus
dbus xml gnus-cloud nnimap nnmail mail-source utf7 netrc nnoo parse-time
gnus-spec gnus-int gnus-range message rmc puny rfc822 mml mml-sec epa
derived epg epg-config mm-decode mm-bodies mm-encode mail-parse rfc2231
mailabbrev gmm-utils mailheader gnus-win gnus nnheader gnus-util rmail
rmail-loaddefs auth-source eieio eieio-core eieio-loaddefs
password-cache json map rfc2047 rfc2045 ietf-drums mail-utils mm-util
mail-prsvr ol-docview doc-view jka-compr image-mode exif ol-bibtex
bibtex iso8601 ol-bbdb ol-w3m tmtxt-async-tasks eshell esh-cmd esh-ext
esh-opt esh-proc esh-io esh-arg esh-module esh-groups esh-util term
shell ehelp recentf tree-widget comp comp-cstr rx cl-seq cl-extra
help-mode wid-edit dired-x wdired org ob ob-tangle ob-ref ob-lob
ob-table ob-exp org-macro org-footnote org-src ob-comint org-pcomplete
pcomplete org-list org-faces org-entities time-date subr-x noutline
outline org-version ob-emacs-lisp ob-core ob-eval org-table ol org-keys
org-compat advice org-macs org-loaddefs format-spec find-func cal-menu
calendar cal-loaddefs edmacro kmacro cl-macs seq gv warnings easy-mmode
byte-opt compile text-property-search comint ansi-color ring bytecomp
byte-compile cconv dired-aux cl-loaddefs cl-lib dired dired-loaddefs
iso-transl tooltip eldoc electric uniquify ediff-hook vc-hooks
lisp-float-type mwheel dos-w32 ls-lisp disp-table term/w32-win w32-win
w32-vars term/common-win tool-bar dnd fontset image regexp-opt fringe
tabulated-list replace newcomment text-mode elisp-mode lisp-mode
prog-mode register page tab-bar menu-bar rfn-eshadow isearch easymenu
timer select scroll-bar mouse jit-lock font-lock syntax font-core
term/tty-colors frame minibuffer cl-generic cham georgian utf-8-lang
misc-lang vietnamese tibetan thai tai-viet lao korean japanese eucjp-ms
cp51932 hebrew greek romanian slovak czech european ethiopic indian
cyrillic chinese composite charscript charprop case-table epa-hook
jka-cmpr-hook help simple abbrev obarray cl-preloaded nadvice button
loaddefs faces cus-face macroexp files window text-properties overlay
sha1 md5 base64 format env code-pages mule custom widget
hashtable-print-readable backquote threads w32notify dbusbind w32 lcms2
multi-tty make-network-process native-compile emacs)

Memory information:
((conses 16 500038 105238)
 (symbols 48 30566 1)
 (strings 32 138236 41347)
 (string-bytes 1 4157999)
 (vectors 16 55072)
 (vector-slots 8 1586872 150266)
 (floats 8 328 354)
 (intervals 56 6434 547)
 (buffers 992 26))