--- libgltf-0.1.0/configure.ac	2016-12-06 19:14:15.000000000 +0000

+++ configure.ac	2018-11-18 01:06:28.591346628 +0000

@@ -65,6 +65,8 @@

 AC_LANG_PUSH([C++])

 save_CPPFLAGS=$CPPFLAGS

 CPPFLAGS="$CPPFLAGS $GLM_CFLAGS"

+CXXFLAGS="$CXXFLAGS -DGLM_ENABLE_EXPERIMENTAL"

+AC_DEFINE([GLM_ENABLE_EXPERIMENTAL], [1], [needed for glm headers])

 AC_CHECK_HEADERS(

  glm/glm.hpp \

  glm/gtc/matrix_inverse.hpp \