master 9b66f875b36 1/2: Fix file-missing error during async native compilation (bug#81223)

branch: master
commit 9b66f875b3624918dcc20281a3632e758abfe4c3
Author: James Cherti <[email protected]>
Commit: Eli Zaretskii <[email protected]>

    Fix file-missing error during async native compilation (bug#81223)
    
    The async native compilation queue can sometimes retain stale jobs
    for files that no longer exist on disk (for example, when files are
    removed during a package upgrade or deletion).  Attempting to resolve
    the target .eln filename for these missing files signals a
    file-missing error.
    * lisp/emacs-lisp/comp-run.el (comp--run-async-workers): Verify
    source files exist before attempting to resolve their .eln paths in
    the dispatch loop.  In the process sentinel, wrap the compilation
    block in a condition-case to catch file-missing errors and prevent
    the async worker queue from stalling.
---
 lisp/emacs-lisp/comp-run.el | 48 ++++++++++++++++++++++++++++++---------------
 1 file changed, 32 insertions(+), 16 deletions(-)

diff --git a/lisp/emacs-lisp/comp-run.el b/lisp/emacs-lisp/comp-run.el
index 64e20327906..203b8531172 100644
--- a/lisp/emacs-lisp/comp-run.el
+++ b/lisp/emacs-lisp/comp-run.el
@@ -279,14 +279,21 @@ display a message."
          do (cl-assert (string-match-p comp-valid-source-re source-file) nil
                        "`comp-files-queue' should be \".el\" files: %s"
                        source-file)
-         when (or native-comp-always-compile
-                  load ; Always compile when the compilation is
-                       ; commanded for late load.
-                  ;; Skip compilation if `comp-el-to-eln-filename' fails
-                  ;; to find a writable directory.
-                  (with-demoted-errors "Async compilation :%S"
-                    (file-newer-than-file-p
-                     source-file (comp-el-to-eln-filename source-file))))
+         when (and
+               ;; Verify that the source file still exists on disk
+               ;; as a regular file before calling
+               ;; `comp-el-to-eln-filename'. This check prevents
+               ;; `file-missing' errors caused by stale jobs in the
+               ;; async compilation queue.
+               (file-regular-p source-file)
+               (or native-comp-always-compile
+                   load ; Always compile when the compilation is
+                        ; commanded for late load.
+                   ;; Skip compilation if `comp-el-to-eln-filename' fails
+                   ;; to find a writable directory.
+                   (with-demoted-errors "Async compilation :%S"
+                     (file-newer-than-file-p
+                      source-file (comp-el-to-eln-filename source-file)))))
          do (let* ((expr `((require 'comp)
                            (setq comp-async-compilation t
                                  warning-fill-column most-positive-fixnum)
@@ -362,14 +369,23 @@ display a message."
                                 source-file)
                                (comp--accept-and-process-async-output process)
                                (ignore-errors (delete-file temp-file))
-                               (let ((eln-file (comp-el-to-eln-filename
-                                                source-file1)))
-                                 (when (and load1
-                                            (zerop (process-exit-status
-                                                    process))
-                                            (file-exists-p eln-file))
-                                   (native-elisp-load eln-file
-                                                      (eq load1 'late))))
+                               ;; Catch the file-missing error that
+                               ;; occurs if the original source file is
+                               ;; deleted while the asynchronous worker
+                               ;; is compiling it. Handling this error
+                               ;; prevents the sentinel from aborting
+                               ;; and ensures the compilation queue
+                               ;; continues processing.
+                               (condition-case nil
+                                   (let ((eln-file (comp-el-to-eln-filename
+                                                    source-file1)))
+                                     (when (and load1
+                                                (zerop (process-exit-status
+                                                        process))
+                                                (file-exists-p eln-file))
+                                       (native-elisp-load eln-file
+                                                          (eq load1 'late))))
+                                 (file-missing nil))
                                (comp--run-async-workers))
                              :noquery (not native-comp-async-query-on-exit))))
               (set-process-thread process nil)