diff --git a/headers/build/os/support/Errors.h b/headers/build/os/support/Errors.h
index a07d8c1386..04d36b41ad 100644
--- a/headers/build/os/support/Errors.h
+++ b/headers/build/os/support/Errors.h
@@ -494,23 +494,44 @@
 	#define ENOEXEC HAIKU_ENOEXEC
 	#define EPIPE HAIKU_EPIPE
 	#define ENOATTR HAIKU_ENOATTR
-
-	#undef errno
-	#define errno (*_haiku_build_errno())
 #elif defined(HAIKU_HOST_PLATFORM_HAIKU)
-#	include <../os/support/Errors.h>
+#	include_next <Errors.h>
 #endif	// ! BUILDING_HAIKU_ERROR_MAPPER
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
-extern int *_haiku_build_errno();
+extern const int _haiku_build_errno();
+extern void _haiku_build_set_errno(int error);
 extern int _haiku_to_host_error(int error);
 
 #ifdef __cplusplus
-}
+} // extern "C"
+
+struct BuildErrnoWrapper {
+	int operator=(int value)
+	{
+		_haiku_build_set_errno(value);
+		return value;
+	}
+	operator int()
+	{
+		return _haiku_build_errno();
+	}
+};
 #endif
 
+/* build-specific code */
+#ifndef BUILDING_HAIKU_ERROR_MAPPER
+#undef errno
+#ifndef __cplusplus
+#define errno (_haiku_build_errno())
+#else
+extern BuildErrnoWrapper build_errno;
+#define errno build_errno
+#endif
+#endif	// ! BUILDING_HAIKU_ERROR_MAPPER
+
 
 #endif	/* _BUILD_ERRORS_H */
diff --git a/src/build/libroot/errors.cpp b/src/build/libroot/errors.cpp
index bd8aa7e299..245e4c46fb 100644
--- a/src/build/libroot/errors.cpp
+++ b/src/build/libroot/errors.cpp
@@ -183,34 +183,38 @@ _haiku_build_strerror(int errnum)
 	return strerror(to_host_error(errnum));
 }
 
-// _haiku_build_errno
-int *
-_haiku_build_errno()
-{
-	static int previousErrno = 0;
-	static int localErrno = 0;
-	static int previousLocalErrno = 0;
-
-	// If the localErrno has been changed and the real errno has not changed
-	// in the meantime, we update errno itself, so that the local update will
-	// be reflected. If errno has changed we always update localErrno.
-	int currentErrno = errno;
-	if (currentErrno == previousErrno) {
-		if (localErrno != previousLocalErrno) {
-			errno = previousErrno = to_host_error(localErrno);
-			previousLocalErrno = localErrno;
-		}
-	} else {
-		previousErrno = currentErrno;
-		previousLocalErrno = localErrno = to_haiku_error(errno);
-	}
-
-	return &localErrno;
-}
-
 // _haiku_to_host_error
 int
 _haiku_to_host_error(int error)
 {
 	return to_host_error(error);
 }
+
+
+// #pragma mark - errno handling
+
+
+BuildErrnoWrapper build_errno;
+static int sPreviousErrno = 0;
+static int sLocalErrno = 0;
+
+
+const int
+_haiku_build_errno()
+{
+	int currentErrno = errno;
+	if (currentErrno != sPreviousErrno) {
+		sPreviousErrno = currentErrno;
+		sLocalErrno = to_haiku_error(currentErrno);
+	}
+
+	return sLocalErrno;
+}
+
+
+void
+_haiku_build_set_errno(int error)
+{
+	sLocalErrno = error;
+	errno = sPreviousErrno = to_host_error(error);
+}