[glibmm/glibmm-2-64] tools/gmmproc.in: Add a comment

[Kjell Ahlstedt <kjellahl src gnome org>]

commit 2ac14c611e55e4cc570af50c959adfffdc4afa76
Author: Kjell Ahlstedt <kjellahlstedt gmail com>
Date:   Wed Apr 8 10:47:53 2020 +0200

    tools/gmmproc.in: Add a comment

 tools/gmmproc.in | 3 +++
 1 file changed, 3 insertions(+)
---
diff --git a/tools/gmmproc.in b/tools/gmmproc.in
index 264955fa..a2293bc6 100644
--- a/tools/gmmproc.in
+++ b/tools/gmmproc.in
@@ -47,6 +47,9 @@ BEGIN {
   # This line must match the install directory
   $main::procdir = $libdir . '/@GLIBMM_MODULE_NAME@/proc';
   $main::m4path = "@M4@";
+  # mm-common/util/build_scripts/check-dllexport-usage.py searches for
+  # the next non-comment line, and checks which version of gmmproc this is.
+  # Don't modify that line in such a way that the search fails.
   $main::glibmm_version = "@PACKAGE_VERSION@";
 
   push(@INC, $main::procdir . '/pm');