diff --git a/src/libutf8/200_decode.c b/src/libutf8/200_decode.c
index f1bc920..414ed50 100644
--- a/src/libutf8/200_decode.c
+++ b/src/libutf8/200_decode.c
@@ -24,7 +24,7 @@ utf8_decode_char2(const char* src, size_t size, size_t* used)
 
     if(!src || !size) {
         errno = EINVAL;
-        return 0;
+        return (wchar_t)-1;
     }
     if(used) *used = 1;
     ch = *src++;
@@ -57,18 +57,18 @@ utf8_decode_char2(const char* src, size_t size, size_t* used)
             ret = ch & 0x01;
         } else {
             errno = EILSEQ;
-            return 0;
+            return (wchar_t)-1;
         }
 
         while(remain--) {
             if(!--size) {
                 errno = EILSEQ;
-                return 0;
+                return (wchar_t)-1;
             }
             ch = *src++;
             if((ch & 0xC0) != 0x80) {
                 errno = EILSEQ;
-                return 0;
+                return (wchar_t)-1;
             }
             ret <<= 6;
             ret |= ch & 0x3F;
@@ -76,7 +76,7 @@ utf8_decode_char2(const char* src, size_t size, size_t* used)
 
         if(ret < min) {
             errno = EILSEQ;
-            return 0;
+            return (wchar_t)-1;
         }
 
         return ret;
@@ -104,7 +104,7 @@ utf8_decode_char2_force(const char* src, size_t size, size_t* used,
 
     if(!src || !size) {
         errno = EINVAL;
-        return 0;
+        return (wchar_t)-1;
     }
     if(used) *used = 1;
     ch = *src++;
@@ -143,7 +143,7 @@ utf8_decode_char2_force(const char* src, size_t size, size_t* used,
             ret |= ch & 0x3F;
         }
 
-        if(ch < min) goto ILSEQ;
+        if(ret < min) goto ILSEQ;
 
         return ret;
     }