[flang] Added windows-include.h wrapper to resolve name conflicts. (#87650)

The header file includes windows.h in a mean-and-lean way to avoid
bringing in names that may conflict with Flang code.

Author: vzakhari

flang/include/flang/Common/windows-include.h

@@ -0,0 +1,25 @@
+//===-- include/flang/Common/windows-include.h ------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// Wrapper around windows.h that works around the name conflicts.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef FORTRAN_COMMON_WINDOWS_INCLUDE_H_
+#define FORTRAN_COMMON_WINDOWS_INCLUDE_H_
+
+#ifdef _WIN32
+
+#define WIN32_LEAN_AND_MEAN
+#define NOMINMAX
+
+#include <windows.h>
+
+#endif // _WIN32
+
+#endif // FORTRAN_COMMON_WINDOWS_INCLUDE_H_

flang/runtime/command.cpp

@@ -16,9 +16,7 @@
 #include <limits>
 
 #ifdef _WIN32
-#define WIN32_LEAN_AND_MEAN
-#define NOMINMAX
-#include <windows.h>
+#include "flang/Common/windows-include.h"
 
 // On Windows GetCurrentProcessId returns a DWORD aka uint32_t
 #include <processthreadsapi.h>

flang/runtime/execute.cpp

@@ -16,9 +16,7 @@
 #include <future>
 #include <limits>
 #ifdef _WIN32
-#define LEAN_AND_MEAN
-#define NOMINMAX
-#include <windows.h>
+#include "flang/Common/windows-include.h"
 #else
 #include <signal.h>
 #include <sys/wait.h>

flang/runtime/file.cpp

@@ -17,9 +17,8 @@
 #include <stdlib.h>
 #include <sys/stat.h>
 #ifdef _WIN32
-#define NOMINMAX
+#include "flang/Common/windows-include.h"
 #include <io.h>
-#include <windows.h>
 #else
 #include <unistd.h>
 #endif

flang/runtime/lock.h

@@ -25,9 +25,7 @@
 #if USE_PTHREADS
 #include <pthread.h>
 #elif defined(_WIN32)
-// Do not define macros for "min" and "max"
-#define NOMINMAX
-#include <windows.h>
+#include "flang/Common/windows-include.h"
 #else
 #include <mutex>
 #endif