diff --git a/Makefile.am b/Makefile.am
index 5a3ff39..c3d0f42 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,6 +1,6 @@
 AUTOMAKE_OPTIONS = foreign no-dependencies
 
-GIT_DEF = -D'GIT_REV="$(shell git describe --tags)"'
+GIT_DEF = -D'GIT_REV="$(shell git describe --tags --dirty)"'
 AM_CFLAGS = -g -O3 -std=gnu99 -ffast-math -DPACKAGE_DATA_DIR=\"$(pkgdatadir)\" $(GIT_DEF)
 
 ACLOCAL_AMFLAGS = -I m4
diff --git a/Makefile.in b/Makefile.in
index c5b0d11..8a9afdc 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -359,7 +359,7 @@ top_build_prefix = @top_build_prefix@
 top_builddir = @top_builddir@
 top_srcdir = @top_srcdir@
 AUTOMAKE_OPTIONS = foreign no-dependencies
-GIT_DEF = -D'GIT_REV="$(shell git describe --tags)"'
+GIT_DEF = -D'GIT_REV="$(shell git describe --tags --dirty)"'
 AM_CFLAGS = -g -O3 -std=gnu99 -ffast-math -DPACKAGE_DATA_DIR=\"$(pkgdatadir)\" $(GIT_DEF)
 ACLOCAL_AMFLAGS = -I m4
 man1_MANS = flam3-animate.man flam3-genome.man flam3-render.man flam3-convert.man