diff --git a/libobs/util/platform.c b/libobs/util/platform.c
index 1041861d6..af4a19a52 100644
--- a/libobs/util/platform.c
+++ b/libobs/util/platform.c
@@ -249,7 +249,7 @@ size_t os_mbs_to_wcs(const char *str, size_t len, wchar_t *dst, size_t dst_size)
 			return 0;
 
 		if (out_len)
-			mbstowcs(dst, str, out_len + 1);
+			out_len = mbstowcs(dst, str, out_len + 1);
 
 		dst[out_len] = 0;
 	}
@@ -274,7 +274,8 @@ size_t os_utf8_to_wcs(const char *str, size_t len, wchar_t *dst,
 			return 0;
 
 		if (out_len)
-			utf8_to_wchar(str, in_len, dst, out_len + 1, 0);
+			out_len = utf8_to_wchar(str, in_len,
+					dst, out_len + 1, 0);
 
 		dst[out_len] = 0;
 	}
@@ -296,7 +297,7 @@ size_t os_wcs_to_mbs(const wchar_t *str, size_t len, char *dst, size_t dst_size)
 			return 0;
 
 		if (out_len)
-			wcstombs(dst, str, out_len + 1);
+			out_len = wcstombs(dst, str, out_len + 1);
 
 		dst[out_len] = 0;
 	}
@@ -321,7 +322,8 @@ size_t os_wcs_to_utf8(const wchar_t *str, size_t len, char *dst,
 			return 0;
 
 		if (out_len)
-			wchar_to_utf8(str, in_len, dst, out_len + 1, 0);
+			out_len = wchar_to_utf8(str, in_len,
+					dst, out_len + 1, 0);
 
 		dst[out_len] = 0;
 	}