diff -ur gsl-1.8.orig/acconfig.h gsl-1.8/acconfig.h
--- gsl-1.8.orig/acconfig.h	2006-03-17 16:53:51.000000000 +0100
+++ gsl-1.8/acconfig.h	2006-03-17 16:53:51.000000000 +0100
@@ -39,10 +39,10 @@
 #undef HAVE_OPENBSD_IEEE_INTERFACE
 #undef HAVE_DARWIN_IEEE_INTERFACE
 
-/* Define this is IEEE comparisons work correctly (e.g. NaN != NaN) */
+/* Define this if IEEE comparisons work correctly (e.g. NaN != NaN) */
 #undef HAVE_IEEE_COMPARISONS
 
-/* Define this is IEEE denormalized numbers are available */
+/* Define this if IEEE denormalized numbers are available */
 #undef HAVE_IEEE_DENORMALS
 
 /* Define a rounding function which moves extended precision values
diff -ur gsl-1.8.orig/config.h.in gsl-1.8/config.h.in
--- gsl-1.8.orig/config.h.in	2006-03-31 20:24:31.000000000 +0200
+++ gsl-1.8/config.h.in	2006-03-31 20:24:31.000000000 +0200
@@ -189,10 +189,10 @@
 #undef HAVE_OPENBSD_IEEE_INTERFACE
 #undef HAVE_DARWIN_IEEE_INTERFACE
 
-/* Define this is IEEE comparisons work correctly (e.g. NaN != NaN) */
+/* Define this if IEEE comparisons work correctly (e.g. NaN != NaN) */
 #undef HAVE_IEEE_COMPARISONS
 
-/* Define this is IEEE denormalized numbers are available */
+/* Define this if IEEE denormalized numbers are available */
 #undef HAVE_IEEE_DENORMALS
 
 /* Define a rounding function which moves extended precision values