From dc2bdc2a21886791451239fd5e31fe8f75deb1ef Mon Sep 17 00:00:00 2001
From: David Girault <dgirault@sevenhugs.com>
Date: Mon, 29 May 2017 11:41:11 +0200
Subject: [PATCH] memp: allow initialization of pool memory if not in standard
 section

---
 src/core/memp.c        | 8 ++++++++
 src/include/lwip/opt.h | 9 +++++++++
 2 files changed, 17 insertions(+)

diff --git a/src/core/memp.c b/src/core/memp.c
index 799ed51b..09c84f5c 100644
--- a/src/core/memp.c
+++ b/src/core/memp.c
@@ -239,6 +239,14 @@ memp_init_pool(const struct memp_desc *desc)
 
   *desc->tab = NULL;
   memp = (struct memp*)LWIP_MEM_ALIGN(desc->base);
+#if MEMP_MEM_INIT
+  /* force memset on pool memory */
+  memset(memp, 0, (size_t)desc->num * (MEMP_SIZE + desc->size
+#if MEMP_OVERFLOW_CHECK
+      + MEMP_SANITY_REGION_AFTER_ALIGNED
+#endif
+    ));
+#endif
   /* create a linked list of memp elements */
   for (i = 0; i < desc->num; ++i) {
     memp->next = *desc->tab;
diff --git a/src/include/lwip/opt.h b/src/include/lwip/opt.h
index 8ee4f3b7..db2322b6 100644
--- a/src/include/lwip/opt.h
+++ b/src/include/lwip/opt.h
@@ -248,6 +248,15 @@
 #define MEMP_MEM_MALLOC                 0
 #endif
 
+/**
+ * MEMP_MEM_INIT==1: Force use of memset to initialize pool memory.
+ * Useful if pool are moved in uninitialized section of memory. This will ensure
+ * default values in pcbs struct are well initialized in all conditions.
+ */
+#if !defined MEMP_MEM_INIT || defined __DOXYGEN__
+#define MEMP_MEM_INIT                 0
+#endif
+
 /**
  * MEM_ALIGNMENT: should be set to the alignment of the CPU
  *    4 byte alignment -> \#define MEM_ALIGNMENT 4