Index: configure.ac
==================================================================
--- configure.ac
+++ configure.ac
@@ -492,10 +492,13 @@
 	[AC_DEFINE(OF_HAVE_MAX_ALIGN_T, 1, [Whether we have max_align_t])])
 
 AC_CHECK_HEADER(stdnoreturn.h,
 	[AC_DEFINE(OF_HAVE_STDNORETURN_H, 1, [Whether we have stdnoreturn.h])])
 
+AC_CHECK_TYPE(wchar_t)
+AC_CHECK_HEADER(wchar.h)
+
 AC_CHECK_SIZEOF(float)
 AC_CHECK_SIZEOF(double)
 AS_IF([test x"$ac_cv_sizeof_float" != x"4" -o x"$ac_cv_sizeof_double" != x"8"],
 	[AC_MSG_ERROR(
 		[Floating point implementation does not conform to IEEE 754!])])

Index: src/of_asprintf.m
==================================================================
--- src/of_asprintf.m
+++ src/of_asprintf.m
@@ -19,11 +19,14 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <stdarg.h>
 #include <stdbool.h>
-#include <wchar.h>
+
+#ifdef HAVE_WCHAR_H
+# include <wchar.h>
+#endif
 
 #ifdef HAVE_ASPRINTF_L
 # include <locale.h>
 #endif
 #ifdef HAVE_XLOCALE_H
@@ -579,18 +582,20 @@
 		case LENGTH_MODIFIER_NONE:
 			tmpLen = asprintf(&tmp, ctx->subformat,
 			    va_arg(ctx->arguments, int));
 			break;
 		case LENGTH_MODIFIER_L:
-#if WINT_MAX >= INT_MAX
+#ifdef HAVE_WCHAR_H
+# if WINT_MAX >= INT_MAX
 			tmpLen = asprintf(&tmp, ctx->subformat,
 			    va_arg(ctx->arguments, wint_t));
-#else
+# else
 			tmpLen = asprintf(&tmp, ctx->subformat,
 			    va_arg(ctx->arguments, int));
-#endif
+# endif
 			break;
+#endif
 		default:
 			return false;
 		}
 
 		break;
@@ -598,14 +603,16 @@
 		switch (ctx->lengthModifier) {
 		case LENGTH_MODIFIER_NONE:
 			tmpLen = asprintf(&tmp, ctx->subformat,
 			    va_arg(ctx->arguments, const char*));
 			break;
+#ifdef HAVE_WCHAR_T
 		case LENGTH_MODIFIER_L:
 			tmpLen = asprintf(&tmp, ctx->subformat,
 			    va_arg(ctx->arguments, const wchar_t*));
 			break;
+#endif
 		default:
 			return false;
 		}
 
 		break;