glog/docs/windows.md

Notes for Windows Users

glog defines the severity level ERROR, which is also defined by windows.h. You can make glog not define INFO, WARNING, ERROR, and FATAL by defining GLOG_NO_ABBREVIATED_SEVERITIES before including glog/logging.h. Even with this macro, you can still use the iostream like logging facilities:

#define GLOG_NO_ABBREVIATED_SEVERITIES
#include <windows.h>
#include <glog/logging.h>

// ...

LOG(ERROR) << "This should work";
LOG_IF(ERROR, x > y) << "This should be also OK";

However, you cannot use INFO, WARNING, ERROR, and FATAL anymore for functions defined in glog/logging.h.

#define GLOG_NO_ABBREVIATED_SEVERITIES
#include <windows.h>
#include <glog/logging.h>

// ...

// This won’t work.
// google::FlushLogFiles(google::ERROR);

// Use this instead.
google::FlushLogFiles(google::GLOG_ERROR);

If you don't need ERROR defined by windows.h, there are a couple of more workarounds which sometimes don't work:

• #!cpp #define WIN32_LEAN_AND_MEAN or NOGDI before #!cpp #include <windows.h>.
• #!cpp #undef ERROR after #!cpp #include <windows.h>.

See this issue for more detail.