From 59e9b71583bc1bf5525dd5e5a8c38f97605e5b54 Mon Sep 17 00:00:00 2001
From: Brett Simmers <bsimmers@fb.com>
Date: Wed, 24 Sep 2014 19:06:38 -0700
Subject: [PATCH] Expand assert in LightProcess::proc_open

Summary: This is occasionally firing in prod. There haven't been any useful
core files but this might give us a hint as to what's going wrong.

Reviewed By: @ptarjan

Differential Revision: D1577087
---
 hphp/util/light-process.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/hphp/util/light-process.cpp b/hphp/util/light-process.cpp
index 28df2e6323d60..2e56ac69c1923 100644
--- a/hphp/util/light-process.cpp
+++ b/hphp/util/light-process.cpp
@@ -701,7 +701,8 @@ pid_t LightProcess::proc_open(const char *cmd, const std::vector<int> &created,
     }
     return -1;
   }
-  always_assert(buf == "success");
+  always_assert_flog(buf == "success",
+                     "Unexpected message from light process: `{}'", buf);
   int64_t pid = -1;
   lwp_read_int64(fin, pid);
   always_assert(pid);