Merge emacs-26

1 files changed, 22 insertions, 0 deletions

diff --git a/lisp/emacs-lisp/bytecomp.el b/lisp/emacs-lisp/bytecomp.el
index 1b42961f1a4..590db570c56 100644
--- a/lisp/emacs-lisp/bytecomp.el
+++ b/lisp/emacs-lisp/bytecomp.el
@@ -1183,7 +1183,29 @@ Each function's symbol gets added to `byte-compile-noruntime-functions'."
 	   (compilation-forget-errors)
 	   pt))))
 
+(defvar byte-compile-log-warning-function
+  #'byte-compile--log-warning-for-byte-compile
+  "Function called when encountering a warning or error.
+Called with arguments (STRING POSITION FILL LEVEL).  STRING is a
+message describing the problem.  POSITION is a buffer position
+where the problem was detected.  FILL is a prefix as in
+`warning-fill-prefix'.  LEVEL is the level of the
+problem (`:warning' or `:error').  POSITION, FILL and LEVEL may be
+nil.")
+
 (defun byte-compile-log-warning (string &optional fill level)
+  "Log a byte-compilation warning.
+STRING, FILL and LEVEL are as described in
+`byte-compile-log-warning-function', which see."
+  (funcall byte-compile-log-warning-function
+           string byte-compile-last-position
+           fill
+           level))
+
+(defun byte-compile--log-warning-for-byte-compile (string &optional
+                                                          _position
+                                                          fill
+                                                          level)
   "Log a message STRING in `byte-compile-log-buffer'.
 Also log the current function and file if not already done.  If
 FILL is non-nil, set `warning-fill-prefix' to four spaces.  LEVEL