bug#24477: 25.1; make-mode: should '$' have punctuation syntax?

[Dima Kogan]

This is a report from this emacs-devel post:

    https://lists.gnu.org/archive/html/emacs-devel/2016-09/msg00414.html

Making a bug report to keep track of this question. The original
message:

I've been working with Makefiles recently, and discovered that $ has
word syntax. This results in odd behaviors. For instance, if you have

    asdf-$(xyz)

in your buffer with the point on 'a', then commands like M-s . or
C-M-SPC select "asdf-$", which makes no sense. Shouldn't $ have
punctuation syntax (attached patch)? Am I missing something obvious
here?

diff --git a/lisp/progmodes/make-mode.el b/lisp/progmodes/make-mode.el
index fb71420..2b4ed85 100644
--- a/lisp/progmodes/make-mode.el
+++ b/lisp/progmodes/make-mode.el
@@ -712,6 +712,7 @@ makefile-mode-syntax-table
     (modify-syntax-entry ?#  "<     " st)
     (modify-syntax-entry ?\n ">     " st)
     (modify-syntax-entry ?= "." st)
+    (modify-syntax-entry ?$ "." st)
     st)
   "Syntax table used in `makefile-mode'.")