diff --git a/.gitignore b/.gitignore
index 363698f1c..76be407b5 100644
--- a/.gitignore
+++ b/.gitignore
@@ -11,12 +11,15 @@
 
 autom4te.cache
 config.cache
+config.guess
 config.h
 config.h.in
 config.log
 config.mk
 config.status
+config.sub
 configure
+install-sh
 
 hfile_*.bundle
 hfile_*.cygdll
diff --git a/configure.ac b/configure.ac
index 9bd1642d7..f473c97e5 100644
--- a/configure.ac
+++ b/configure.ac
@@ -137,9 +137,9 @@ AC_ARG_ENABLE([s3],
                   [support Amazon AWS S3 URLs])],
   [], [enable_s3=check])
 
-test -n "$host_alias" || host_alias=unknown-`uname -s`
-AC_MSG_CHECKING([shared library type for $host_alias])
-case $host_alias in
+basic_host=${host_alias:-unknown-`uname -s`}
+AC_MSG_CHECKING([shared library type for $basic_host])
+case $basic_host in
   *-cygwin* | *-CYGWIN*)
     host_result="Cygwin DLL"
     PLATFORM=CYGWIN