diff --git a/source/compiler/CMakeLists.txt b/source/compiler/CMakeLists.txt
index a2eb8a9..ab7d9fe 100644
--- a/source/compiler/CMakeLists.txt
+++ b/source/compiler/CMakeLists.txt
@@ -22,6 +22,17 @@ if(HAVE_ALLOCA_H)
   add_definitions(-DHAVE_ALLOCA_H)
 endif()
 
+# check for optional library functions
+include(CheckFunctionExists)
+check_function_exists(strlcpy HAVE_STRLCPY)
+if(HAVE_STRLCPY)
+  add_definitions(-DHAVE_STRLCPY)
+endif()
+check_function_exists(strlcat HAVE_STRLCAT)
+if(HAVE_STRLCAT)
+  add_definitions(-DHAVE_STRLCAT)
+endif()
+
 if(MSVC)
   add_definitions(-D_CRT_SECURE_NO_WARNINGS /J)
 endif()
diff --git a/source/compiler/lstring.c b/source/compiler/lstring.c
index b21f352..bbd359f 100644
--- a/source/compiler/lstring.c
+++ b/source/compiler/lstring.c
@@ -7,7 +7,7 @@
 
 #include "lstring.h"
 
-#if !defined HAVE_SAFESTR
+#if !defined HAVE_STRLCPY
 
 /*	$OpenBSD: strlcpy.c,v 1.10 2005/08/08 08:05:37 espie Exp $	*/
 
@@ -63,6 +63,10 @@ strlcpy(char *dst, const char *src, size_t siz)
 	return(s - src - 1);	/* count does not include NUL */
 }
 
+#endif /* if !defined HAVE_STRLCPY */
+
+#if !defined HAVE_STRLCAT
+
 /*	$OpenBSD: strlcat.c,v 1.13 2005/08/08 08:05:37 espie Exp $	*/
 
 /*
@@ -121,4 +125,4 @@ strlcat(char *dst, const char *src, size_t siz)
 	return(dlen + (s - src));	/* count does not include NUL */
 }
 
-#endif /* #if !defined HAVE_SAFESTR */
+#endif /* #if !defined HAVE_STRLCAT */
diff --git a/source/compiler/lstring.h b/source/compiler/lstring.h
index 1e7e048..25c0873 100644
--- a/source/compiler/lstring.h
+++ b/source/compiler/lstring.h
@@ -7,11 +7,20 @@
   #define HAVE_SAFESTR
 #endif
 
-#if !defined HAVE_SAFESTR
+#if defined HAVE_SAFESTR
+  #define HAVE_STRLCPY
+  #define HAVE_STRLCAT
+#endif
+
+#if !defined HAVE_STRLCPY
 
 size_t
 strlcpy(char *dst, const char *src, size_t siz);
 
+#endif
+
+#if !defined HAVE_STRLCAT
+
 size_t
 strlcat(char *dst, const char *src, size_t siz);