From a48b8169305527f480bfae0f413bd48f818b6bf9 Mon Sep 17 00:00:00 2001
From: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Date: Mon, 21 Aug 2017 11:25:33 +0200
Subject: [PATCH] make it compile with glibc-2.26 with an explicit cast to bool

With glibc-2.26, openslam_gmapping failed to compile with:
```
| [...]/gridfastslam/gfsreader.cpp: In member function 'virtual void GMapping::GFSReader::RawOdometryRecord::read(std::istream&)':
| [...]/gridfastslam/gfsreader.cpp:79:3: error: no match for 'operator==' (operand types are 'std::istream {aka std::basic_istream<char>}' and 'int')
|    assert(is);
|    ^
```

Hence, this commit explicitly casts to bool, so that the assert annotation compiles
properly again.

Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
---
 gridfastslam/gfsreader.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gridfastslam/gfsreader.cpp b/gridfastslam/gfsreader.cpp
index 8b16427..c83f721 100644
--- a/gridfastslam/gfsreader.cpp
+++ b/gridfastslam/gfsreader.cpp
@@ -76,7 +76,7 @@ void RawOdometryRecord::read(istream& is){
   is >> pose.y;
   is >> pose.theta;
   time = 0;
-  assert(is);
+  assert(static_cast<bool>(is));
     is >> time;
  
 }