diff --git a/configure b/configure
index 707eb12..c363079 100755
--- a/configure
+++ b/configure
@@ -237,13 +237,49 @@ test -n "$CC" || { echo "$0: cannot find a C compiler" ; exit 1 ; }
 
 printf "checking whether C compiler works... "
 echo "typedef int x;" > "$tmpc"
-if output=$($CC $CPPFLAGS $CFLAGS -c -o /dev/null "$tmpc" 2>&1) ; then
+if output=$($CC -c -o /dev/null "$tmpc" 2>&1) ; then
 printf "yes\n"
 else
 printf "no; compiler output follows:\n%s\n" "$output"
 exit 1
 fi
 
+if test x"$shared" != xno ; then
+  printf "checking whether linker works... "
+  echo "int main(void) { return 0; }" > "$tmpc"
+  if output=$($CC -nostdlib -shared -o /dev/null "$tmpc" 2>&1) ; then
+  printf "yes\n"
+  else
+  if test x"$shared" = xyes ; then
+  printf "no; compiler output follows:\n%s\n" "$output"
+  exit 1
+  else
+  printf "no; shared library disabled\n"
+  shared=no
+  fi
+  fi
+fi
+
+printf "checking whether CFLAGS and CPPFLAGS are sane... "
+echo "typedef int x;" > "$tmpc"
+if output=$($CC $CFLAGS $CPPFLAGS -c -o /dev/null "$tmpc" 2>&1) ; then
+printf "yes\n"
+else
+printf "no; compiler output follows:\n%s\n" "$output"
+exit 1
+fi
+
+if test x"$shared" != xno ; then
+  printf "checking whether LDFLAGS are sane... "
+  echo "int main(void) { return 0; }" > "$tmpc"
+  if output=$($CC $LDFLAGS -nostdlib -shared -o /dev/null "$tmpc" 2>&1) ; then
+  printf "yes\n"
+  else
+  printf "no; compiler output follows:\n%s\n" "$output"
+  exit 1
+  fi
+fi
+
 #
 # Figure out options to force errors on unknown flags.
 #