diff --git a/configure.ac b/configure.ac
index 96a6a656..adb57405 100644
--- a/configure.ac
+++ b/configure.ac
@@ -257,6 +257,9 @@ if test "x$ac_cv_lib_glut_glutGameModeString" = "xno"; then
     exit 1
 fi
 
+AC_CHECK_LIB(tiff, TIFFOpen,,,)
+AM_CONDITIONAL(HAVE_LIBTIFF, test x$ac_cv_lib_tiff_TIFFOpen = xyes)
+
 AC_LANG_PUSH(C++)
 # needed for plib 1.8.x or later
 AC_CHECK_LIB(plibul, ulInit,,,)
diff --git a/src/Lib/HGT/Makefile.am b/src/Lib/HGT/Makefile.am
index 09188874..b4ee8cb9 100644
--- a/src/Lib/HGT/Makefile.am
+++ b/src/Lib/HGT/Makefile.am
@@ -8,7 +8,7 @@ testhgt_SOURCES = testhgt.cxx
 
 testhgt_LDADD = \
 	$(top_builddir)/src/Lib/HGT/libHGT.a \
-	-lsgbucket -lsgmisc -lsgdebug -lz
+	-lsgbucket -lsgmisc -lsgdebug -lz -lplibul
 
 INCLUDES = -I$(top_srcdir)/src
 
diff --git a/src/Lib/HGT/hgt.cxx b/src/Lib/HGT/hgt.cxx
index 55fe4ee0..61c39757 100644
--- a/src/Lib/HGT/hgt.cxx
+++ b/src/Lib/HGT/hgt.cxx
@@ -87,7 +87,7 @@ TGHgt::open ( const SGPath &f ) {
         if ( file_name.extension() == "zip" ) {
             // extract the .zip file to /tmp and point the file name
             // to the extracted file
-	    SGPath tmp_dir = tempnam( 0, "hgt" );
+	    SGPath tmp_dir = string( tempnam( 0, "hgt" ) );
 	    tmp_dir.append( "dummy" );
 	    tmp_dir.create_dir( 0700 );
 	    cout << "Extracting " << file_name.str() << " to " << tmp_dir.dir() << endl;
diff --git a/src/Prep/DemChop/.gitignore b/src/Prep/DemChop/.gitignore
index 7a1dbdfc..bae6e7fb 100644
--- a/src/Prep/DemChop/.gitignore
+++ b/src/Prep/DemChop/.gitignore
@@ -1,4 +1,5 @@
 demchop
 fillvoids
 hgtchop
+srtmchop
 testassem
diff --git a/src/Prep/DemChop/Makefile.am b/src/Prep/DemChop/Makefile.am
index 9e38595a..06d357ba 100644
--- a/src/Prep/DemChop/Makefile.am
+++ b/src/Prep/DemChop/Makefile.am
@@ -23,7 +23,10 @@
 #---------------------------------------------------------------------------
 
 
-bin_PROGRAMS = demchop hgtchop srtmchop fillvoids testassem
+bin_PROGRAMS = demchop hgtchop fillvoids testassem
+if HAVE_LIBTIFF
+bin_PROGRAMS+=srtmchop
+endif
 
 demchop_SOURCES = \
 	demchop.cxx point2d.hxx
@@ -38,16 +41,18 @@ hgtchop_SOURCES = \
 
 hgtchop_LDADD = \
 	$(top_builddir)/src/Lib/HGT/libHGT.a \
-	-lsgbucket -lsgmisc -lsgdebug -lsgxml -lz
+	-lsgbucket -lsgmisc -lsgdebug -lsgxml -lz -lplibul
 	$(base_LIBS)
 
+if HAVE_LIBTIFF
 srtmchop_SOURCES = \
 	srtmchop.cxx point2d.hxx
 
 srtmchop_LDADD = \
 	$(top_builddir)/src/Lib/HGT/libHGT.a \
-	-lsgbucket -lsgmisc -lsgdebug -lsgxml -lz
+	-lsgbucket -lsgmisc -lsgdebug -lsgxml -lz -lplibul -ltiff
 	$(base_LIBS)
+endif
 
 fillvoids_SOURCES = \
 	fillvoids.cxx
diff --git a/src/Prep/DemChop/srtmchop.cxx b/src/Prep/DemChop/srtmchop.cxx
index d213315a..f05d4a27 100644
--- a/src/Prep/DemChop/srtmchop.cxx
+++ b/src/Prep/DemChop/srtmchop.cxx
@@ -168,7 +168,7 @@ bool TGSrtmTiff::open( const SGPath &f ) {
     if ( ext == "zip" ) {
         // extract the .zip file to /tmp and point the file name
         // to the extracted file
-	SGPath tmp_dir = tempnam( 0, "hgt" );
+	SGPath tmp_dir = string( tempnam( 0, "hgt" ) );
 	tmp_dir.append( "dummy" );
 	tmp_dir.create_dir( 0700 );
         cout << "Extracting " << file_name.str() << " to " << tmp_dir.dir() << endl;