diff -rup postgresql-7.4.orig/src/include/utils/builtins.h postgresql-7.4/src/include/utils/builtins.h
--- postgresql-7.4.orig/src/include/utils/builtins.h	2003-11-19 09:37:03.111310400 -0500
+++ postgresql-7.4/src/include/utils/builtins.h	2003-11-19 09:37:12.164328000 -0500
@@ -231,7 +231,7 @@ extern Datum btname_pattern_cmp(PG_FUNCT
 extern Datum bttext_pattern_cmp(PG_FUNCTION_ARGS);
 
 /* float.c */
-extern int	extra_float_digits;
+extern DLLIMPORT int	extra_float_digits;
 
 extern Datum float4in(PG_FUNCTION_ARGS);
 extern Datum float4out(PG_FUNCTION_ARGS);