diff --git a/storage/innobase/handler/handler0alter.cc b/storage/innobase/handler/handler0alter.cc
index 29485f22079..d3f8dbbfd29 100644
--- a/storage/innobase/handler/handler0alter.cc
+++ b/storage/innobase/handler/handler0alter.cc
@@ -4165,7 +4165,8 @@ innobase_build_col_map(
 		    == dict_table_get_n_cols(new_table));
 	DBUG_ASSERT(table->s->stored_fields > 0);
 
-	const size_t old_n_v_cols = table->s->fields - table->s->stored_fields;
+	const uint old_n_v_cols = uint(table->s->fields
+				       - table->s->stored_fields);
 	DBUG_ASSERT(old_n_v_cols == old_table->n_v_cols
 		    || table->s->frm_version < FRM_VER_EXPRESSSIONS);
 	DBUG_ASSERT(!old_n_v_cols || table->s->virtual_fields);
diff --git a/storage/innobase/include/pars0sym.h b/storage/innobase/include/pars0sym.h
index c9a5bb5fac2..5108db79322 100644
--- a/storage/innobase/include/pars0sym.h
+++ b/storage/innobase/include/pars0sym.h
@@ -1,7 +1,7 @@
 /*****************************************************************************
 
 Copyright (c) 1997, 2016, Oracle and/or its affiliates. All Rights Reserved.
-Copyright (c) 2017, 2018, MariaDB Corporation.
+Copyright (c) 2017, 2019, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -224,7 +224,7 @@ struct sym_tab_t{
 					/*!< SQL string to parse */
 	size_t			string_len;
 					/*!< SQL string length */
-	int			next_char_pos;
+	size_t			next_char_pos;
 					/*!< position of the next character in
 					sql_string to give to the lexical
 					analyzer */
diff --git a/storage/innobase/log/log0recv.cc b/storage/innobase/log/log0recv.cc
index 70a705cd026..4840bf3088a 100644
--- a/storage/innobase/log/log0recv.cc
+++ b/storage/innobase/log/log0recv.cc
@@ -445,14 +445,29 @@ fil_name_parse(
 	and end in .ibd. */
 	bool corrupt = is_predefined_tablespace(space_id)
 		|| len < sizeof "/a.ibd\0"
-		|| (!first_page_no != !memcmp(ptr + len - 5, DOT_IBD, 5))
-		|| memchr(ptr, OS_PATH_SEPARATOR, len) == NULL;
+		|| (!first_page_no != !memcmp(ptr + len - 5, DOT_IBD, 5));
+
+	if (!corrupt && !memchr(ptr, OS_PATH_SEPARATOR, len)) {
+		if (byte* c = static_cast<byte*>
+		    (memchr(ptr, OS_PATH_SEPARATOR_ALT, len))) {
+			ut_ad(c >= ptr);
+			ut_ad(c < ptr + len);
+			do {
+				*c = OS_PATH_SEPARATOR;
+			} while ((c = static_cast<byte*>
+				  (memchr(ptr, OS_PATH_SEPARATOR_ALT,
+					  len - ulint(c - ptr)))) != NULL);
+		} else {
+			corrupt = true;
+		}
+	}
 
 	byte*	end_ptr	= ptr + len;
 
 	switch (type) {
 	default:
 		ut_ad(0); // the caller checked this
+		/* fall through */
 	case MLOG_FILE_NAME:
 		if (corrupt) {
 			ib::error() << "MLOG_FILE_NAME incorrect:" << ptr;
@@ -513,8 +528,25 @@ fil_name_parse(
 
 		corrupt = corrupt
 			|| new_len < sizeof "/a.ibd\0"
-			|| memcmp(new_name + new_len - 5, DOT_IBD, 5) != 0
-			|| !memchr(new_name, OS_PATH_SEPARATOR, new_len);
+			|| memcmp(new_name + new_len - 5, DOT_IBD, 5) != 0;
+
+		if (!corrupt && !memchr(new_name, OS_PATH_SEPARATOR, new_len)) {
+			if (byte* c = static_cast<byte*>
+			    (memchr(new_name, OS_PATH_SEPARATOR_ALT,
+				    new_len))) {
+				ut_ad(c >= new_name);
+				ut_ad(c < new_name + new_len);
+				do {
+					*c = OS_PATH_SEPARATOR;
+				} while ((c = static_cast<byte*>
+					  (memchr(ptr, OS_PATH_SEPARATOR_ALT,
+						  new_len
+						  - ulint(c - new_name))))
+					 != NULL);
+			} else {
+				corrupt = true;
+			}
+		}
 
 		if (corrupt) {
 			ib::error() << "MLOG_FILE_RENAME2 new_name incorrect:" << ptr
@@ -1545,8 +1577,7 @@ parse_log:
 		break;
 	case MLOG_ZIP_PAGE_COMPRESS:
 		/* Allow anything in page_type when creating a page. */
-		ptr = page_zip_parse_compress(ptr, end_ptr,
-					      page, page_zip);
+		ptr = page_zip_parse_compress(ptr, end_ptr, page, page_zip);
 		break;
 	case MLOG_ZIP_PAGE_COMPRESS_NO_DATA:
 		if (NULL != (ptr = mlog_parse_index(
diff --git a/storage/innobase/pars/pars0pars.cc b/storage/innobase/pars/pars0pars.cc
index 4c3343a60ae..363ca69a09b 100644
--- a/storage/innobase/pars/pars0pars.cc
+++ b/storage/innobase/pars/pars0pars.cc
@@ -2069,9 +2069,8 @@ pars_get_lex_chars(
 	size_t	max_size)	/*!< in: maximum number of characters which fit
 				in the buffer */
 {
-	size_t len = size_t(
-		pars_sym_tab_global->string_len
-		- pars_sym_tab_global->next_char_pos);
+	size_t len = pars_sym_tab_global->string_len
+		- pars_sym_tab_global->next_char_pos;
 	if (len == 0) {
 		return(0);
 	}
@@ -2081,7 +2080,7 @@ pars_get_lex_chars(
 	}
 
 	memcpy(buf, pars_sym_tab_global->sql_string
-	       + pars_sym_tab_global->next_char_pos, ulint(len));
+	       + pars_sym_tab_global->next_char_pos, len);
 
 	pars_sym_tab_global->next_char_pos += len;