debian/changelog

+grass (7.4.2-2) unstable; urgency=medium
+
+  * Add libegl1-mesa-dev to build dependencies for KHR/khrplatform.h.
+    GL/glext.h from mesa-common-dev includes this header, but lacks dependency.
+
+ -- Bas Couwenberg <sebastic@debian.org>  Tue, 20 Nov 2018 17:51:16 +0100
+
 grass (7.4.2-1) unstable; urgency=medium
 
   * New upstream release.

debian/control

@@ -16,6 +16,7 @@ Build-Depends: autoconf2.13,
                libblas-dev,
                libbz2-dev,
                libcairo2-dev,
+               libegl1-mesa-dev,
                libfftw3-dev,
                libfreetype6-dev,
                libgdal-dev (>= 2.0),