diff --git a/fdbrpc/ContinuousSample.h b/fdbrpc/ContinuousSample.h
index 54ff1b109..577c228ae 100644
--- a/fdbrpc/ContinuousSample.h
+++ b/fdbrpc/ContinuousSample.h
@@ -26,6 +26,7 @@
 #include "flow/IRandom.h"
 #include <vector>
 #include <algorithm>
+#include <cmath>
 
 template <class T>
 class ContinuousSample {
diff --git a/fdbrpc/Smoother.h b/fdbrpc/Smoother.h
index 3ed8e6e98..fb4694750 100644
--- a/fdbrpc/Smoother.h
+++ b/fdbrpc/Smoother.h
@@ -23,6 +23,7 @@
 #pragma once
 
 #include "flow/flow.h"
+#include <cmath>
 
 struct Smoother {
 	// Times (t) are expected to be nondecreasing
@@ -90,4 +91,4 @@ struct TimerSmoother {
 	double time, total, estimate;
 };
 
-#endif
\ No newline at end of file
+#endif
diff --git a/fdbrpc/libcoroutine/Coro.c b/fdbrpc/libcoroutine/Coro.c
index cbfdc8fde..9993cee44 100644
--- a/fdbrpc/libcoroutine/Coro.c
+++ b/fdbrpc/libcoroutine/Coro.c
@@ -66,6 +66,8 @@ VALGRIND_STACK_DEREGISTER((coro)->valgrindStackId)
 #define STACK_DEREGISTER(coro)
 #endif
 
+#pragma GCC diagnostic ignored "-Wreturn-local-addr"
+
 // Define outside
 extern intptr_t g_stackYieldLimit;
 
diff --git a/fdbserver/Knobs.cpp b/fdbserver/Knobs.cpp
index 819c513c6..acfbfe7db 100644
--- a/fdbserver/Knobs.cpp
+++ b/fdbserver/Knobs.cpp
@@ -20,6 +20,7 @@
 
 #include "Knobs.h"
 #include "fdbrpc/Locality.h"
+#include <cmath>
 
 ServerKnobs const* SERVER_KNOBS = new ServerKnobs();
 
diff --git a/flow/Knobs.cpp b/flow/Knobs.cpp
index b485a8495..82541d439 100644
--- a/flow/Knobs.cpp
+++ b/flow/Knobs.cpp
@@ -20,6 +20,7 @@
 
 #include "Knobs.h"
 #include "flow/flow.h"
+#include <cmath>
 
 FlowKnobs const* FLOW_KNOBS = new FlowKnobs();
 
diff --git a/flow/Platform.cpp b/flow/Platform.cpp
index 69dac889a..62bda9edb 100644
--- a/flow/Platform.cpp
+++ b/flow/Platform.cpp
@@ -40,6 +40,7 @@
 #include <algorithm>
 
 #include <sys/types.h>
+#include <sys/sysmacros.h>
 #include <time.h>
 #include <sys/stat.h>
 #include <fcntl.h>
@@ -623,7 +624,7 @@ void getDiskStatistics(std::string const& directory, uint64_t& currentIOs, uint6
 		unsigned int minorId;
 		disk_stream >> majorId;
 		disk_stream >> minorId;
-		if(majorId == (unsigned int) major(buf.st_dev) && minorId == (unsigned int) minor(buf.st_dev)) {
+		if(majorId == (unsigned int) gnu_dev_major(buf.st_dev) && minorId == (unsigned int) gnu_dev_minor(buf.st_dev)) {
 			std::string ignore;
 			uint64_t rd_ios;	/* # of reads completed */
 			//	    This is the total number of reads completed successfully.
diff --git a/flow/Profiler.actor.cpp b/flow/Profiler.actor.cpp
index 27af613e6..69f38c237 100644
--- a/flow/Profiler.actor.cpp
+++ b/flow/Profiler.actor.cpp
@@ -35,8 +35,6 @@
 
 extern volatile int profilingEnabled;
 
-static uint64_t gettid() { return syscall(__NR_gettid); }
-
 struct SignalClosure {
 	void (* func)(int, siginfo_t*, void*, void*);
 	void *userdata;
diff --git a/flow/TDMetric.actor.h b/flow/TDMetric.actor.h
index 5421b83b5..711a96093 100755
--- a/flow/TDMetric.actor.h
+++ b/flow/TDMetric.actor.h
@@ -36,6 +36,7 @@
 #include "CompressedInt.h"
 #include <algorithm>
 #include <functional>
+#include <cmath>
 
 struct MetricNameRef {
 	MetricNameRef() {}
diff --git a/flow/flow.h b/flow/flow.h
index 0c220afae..f685fbc63 100644
--- a/flow/flow.h
+++ b/flow/flow.h
@@ -248,19 +248,6 @@ public:
 		}
 	}
 
-	bool operator == (ErrorOr const& o) const {
-		return error == o.error && (!present() || get() == o.get());
-	}
-	bool operator != (ErrorOr const& o) const {
-		return !(*this == o);
-	}
-
-	bool operator < (ErrorOr const& o) const {
-		if (error != o.error) return error < o.error;
-		if (!present()) return false;
-		return get() < o.get();
-	}
-
 	bool isError() const { return error.code() != invalid_error_code; }
 	bool isError(int code) const { return error.code() == code; }
 	Error getError() const { ASSERT(isError()); return error; }