--- a/src/mbyte.c
+++ b/src/mbyte.c
@@ -809,17 +809,17 @@ bomb_size(void)
     void
 remove_bom(char_u *s)
 {
-    if (enc_utf8)
+    if (!enc_utf8)
+	return;
+
+    char_u *p = s;
+
+    while ((p = vim_strbyte(p, 0xef)) != NULL)
     {
-	char_u *p = s;
-
-	while ((p = vim_strbyte(p, 0xef)) != NULL)
-	{
-	    if (p[1] == 0xbb && p[2] == 0xbf)
-		STRMOVE(p, p + 3);
-	    else
-		++p;
-	}
+	if (p[1] == 0xbb && p[2] == 0xbf)
+	    STRMOVE(p, p + 3);
+	else
+	    ++p;
     }
 }
 #endif
@@ -4590,56 +4590,56 @@ enc_canonize(char_u *enc)
 
     // copy "enc" to allocated memory, with room for two '-'
     r = alloc(STRLEN(enc) + 3);
-    if (r != NULL)
+    if (r == NULL)
+	return NULL;
+
+    // Make it all lower case and replace '_' with '-'.
+    p = r;
+    for (s = enc; *s != NUL; ++s)
+    {
+	if (*s == '_')
+	    *p++ = '-';
+	else
+	    *p++ = TOLOWER_ASC(*s);
+    }
+    *p = NUL;
+
+    // Skip "2byte-" and "8bit-".
+    p = enc_skip(r);
+
+    // Change "microsoft-cp" to "cp".  Used in some spell files.
+    if (STRNCMP(p, "microsoft-cp", 12) == 0)
+	STRMOVE(p, p + 10);
+
+    // "iso8859" -> "iso-8859"
+    if (STRNCMP(p, "iso8859", 7) == 0)
     {
-	// Make it all lower case and replace '_' with '-'.
-	p = r;
-	for (s = enc; *s != NUL; ++s)
-	{
-	    if (*s == '_')
-		*p++ = '-';
-	    else
-		*p++ = TOLOWER_ASC(*s);
-	}
-	*p = NUL;
-
-	// Skip "2byte-" and "8bit-".
-	p = enc_skip(r);
-
-	// Change "microsoft-cp" to "cp".  Used in some spell files.
-	if (STRNCMP(p, "microsoft-cp", 12) == 0)
-	    STRMOVE(p, p + 10);
-
-	// "iso8859" -> "iso-8859"
-	if (STRNCMP(p, "iso8859", 7) == 0)
-	{
-	    STRMOVE(p + 4, p + 3);
-	    p[3] = '-';
-	}
-
-	// "iso-8859n" -> "iso-8859-n"
-	if (STRNCMP(p, "iso-8859", 8) == 0 && isdigit(p[8]))
-	{
-	    STRMOVE(p + 9, p + 8);
-	    p[8] = '-';
-	}
-
-	// "latin-N" -> "latinN"
-	if (STRNCMP(p, "latin-", 6) == 0)
-	    STRMOVE(p + 5, p + 6);
-
-	if (enc_canon_search(p) >= 0)
-	{
-	    // canonical name can be used unmodified
-	    if (p != r)
-		STRMOVE(r, p);
-	}
-	else if ((i = enc_alias_search(p)) >= 0)
-	{
-	    // alias recognized, get canonical name
-	    vim_free(r);
-	    r = vim_strsave((char_u *)enc_canon_table[i].name);
-	}
+	STRMOVE(p + 4, p + 3);
+	p[3] = '-';
+    }
+
+    // "iso-8859n" -> "iso-8859-n"
+    if (STRNCMP(p, "iso-8859", 8) == 0 && isdigit(p[8]))
+    {
+	STRMOVE(p + 9, p + 8);
+	p[8] = '-';
+    }
+
+    // "latin-N" -> "latinN"
+    if (STRNCMP(p, "latin-", 6) == 0)
+	STRMOVE(p + 5, p + 6);
+
+    if (enc_canon_search(p) >= 0)
+    {
+	// canonical name can be used unmodified
+	if (p != r)
+	    STRMOVE(r, p);
+    }
+    else if ((i = enc_alias_search(p)) >= 0)
+    {
+	// alias recognized, get canonical name
+	vim_free(r);
+	r = vim_strsave((char_u *)enc_canon_table[i].name);
     }
     return r;
 }
@@ -5269,26 +5269,26 @@ convert_input_safe(
 
     d = string_convert_ext(&input_conv, ptr, &dlen,
 					restp == NULL ? NULL : &unconvertlen);
-    if (d != NULL)
+    if (d == NULL)
+	return dlen;
+
+    if (dlen <= maxlen)
     {
-	if (dlen <= maxlen)
+	if (unconvertlen > 0)
 	{
-	    if (unconvertlen > 0)
-	    {
-		// Move the unconverted characters to allocated memory.
-		*restp = alloc(unconvertlen);
-		if (*restp != NULL)
-		    mch_memmove(*restp, ptr + len - unconvertlen, unconvertlen);
-		*restlenp = unconvertlen;
-	    }
-	    mch_memmove(ptr, d, dlen);
+	    // Move the unconverted characters to allocated memory.
+	    *restp = alloc(unconvertlen);
+	    if (*restp != NULL)
+		mch_memmove(*restp, ptr + len - unconvertlen, unconvertlen);
+	    *restlenp = unconvertlen;
 	}
-	else
-	    // result is too long, keep the unconverted text (the caller must
-	    // have done something wrong!)
-	    dlen = len;
-	vim_free(d);
+	mch_memmove(ptr, d, dlen);
     }
+    else
+	// result is too long, keep the unconverted text (the caller must
+	// have done something wrong!)
+	dlen = len;
+    vim_free(d);
     return dlen;
 }