[flang] Don't redefine pid_t on MinGW-w64. (#130288)

Author: MehdiChinoune

flang-rt/lib/runtime/command.cpp

@@ -21,9 +21,11 @@
 #define getcwd _getcwd
 #define PATH_MAX MAX_PATH
 
+#ifdef _MSC_VER
 // On Windows GetCurrentProcessId returns a DWORD aka uint32_t
 #include <processthreadsapi.h>
 inline pid_t getpid() { return GetCurrentProcessId(); }
+#endif
 #else
 #include <unistd.h> //getpid()
 

flang/include/flang/Optimizer/Builder/Runtime/RTBuilder.h

@@ -30,7 +30,7 @@
 #include <cstdint>
 #include <functional>
 
-#ifdef _WIN32
+#ifdef _MSC_VER
 // On Windows* OS GetCurrentProcessId returns DWORD aka uint32_t
 typedef std::uint32_t pid_t;
 #endif

flang/include/flang/Runtime/command.h

@@ -12,7 +12,7 @@
 #include "flang/Runtime/entry-names.h"
 #include <cstdint>
 
-#ifdef _WIN32
+#ifdef _MSC_VER
 // On Windows* OS GetCurrentProcessId returns DWORD aka uint32_t
 typedef std::uint32_t pid_t;
 #else