support pmem's experimental rpmem

rpmem requires a fairly new libfabirc and a patch to make gcc7 happy

packages/pmem/0001-benchmark-fix-buffer-overflow-in-rpmem_persist.patch

+From 7e180535a3c3e3c38270474168aba4492feaa14a Mon Sep 17 00:00:00 2001
+From: Krzysztof Czurylo <krzysztof.czurylo@intel.com>
+Date: Tue, 18 Jul 2017 13:14:50 +0200
+Subject: [PATCH] benchmark: fix buffer overflow in rpmem_persist
+
+Ref: pmem/issues#600
+---
+ src/benchmarks/rpmem_persist.cpp | 6 +-----
+ 1 file changed, 1 insertion(+), 5 deletions(-)
+
+diff --git a/src/benchmarks/rpmem_persist.cpp b/src/benchmarks/rpmem_persist.cpp
+index 8f10a5c4..a7872ae5 100644
+--- a/src/benchmarks/rpmem_persist.cpp
++++ b/src/benchmarks/rpmem_persist.cpp
+@@ -284,11 +284,7 @@ rpmem_poolset_init(const char *path, struct rpmem_bench *mb,
+ 
+ 	struct rpmem_pool_attr attr;
+ 	memset(&attr, 0, sizeof(attr));
+-	int ret = snprintf(attr.signature, sizeof(attr.signature), "PMEMBENCH");
+-	if (ret < 0) {
+-		perror("snprintf");
+-		return -1;
+-	}
++	memcpy(attr.signature, "PMEMBNCH", sizeof(attr.signature));
+ 
+ 	/* read and validate poolset */
+ 	if (util_poolset_read(&set, path)) {
+-- 
+2.14.1
+

packages/pmem/package.py

@@ -36,5 +36,10 @@ class Pmem(Package):
     version('1.2.3',       '5e3fba2bf4fd6b0c16db4e91d32df4b0')
     version('1.2.2',       'f02832e9e0e2617e2c996f7b83b2e5ec')
 
+    # experimental rpmem
+    depends_on('libfabric@1.4.2:')
+    # gcc7 warns about buffer overflows
+    patch('0001-benchmark-fix-buffer-overflow-in-rpmem_persist.patch')
+
     def install(self, spec, prefix):
         make("install", "prefix=%s" % prefix)