diff --git a/lldb/include/lldb/Host/windows/PosixApi.h b/lldb/include/lldb/Host/windows/PosixApi.h
--- a/lldb/include/lldb/Host/windows/PosixApi.h
+++ b/lldb/include/lldb/Host/windows/PosixApi.h
@@ -45,6 +45,15 @@
 #define S_IRWXG 0
 #define S_IRWXO 0
 
+#ifdef __MINGW32__
+// pyconfig.h typedefs this.  We require python headers to be included before
+// any LLDB headers, but there's no way to prevent python's pid_t definition
+// from leaking, so this is the best option.
+#ifndef NO_PID_T
+#include <sys/types.h>
+#endif
+#endif // __MINGW32__
+
 #ifdef _MSC_VER
 
 // PRIxxx format macros for printf()
@@ -80,6 +89,8 @@
 char *strcasestr(const char *s, const char *find);
 char *realpath(const char *name, char *resolved);
 
+#ifdef _MSC_VER
+
 int usleep(uint32_t useconds);
 char *basename(char *path);
 char *dirname(char *path);
@@ -87,6 +98,8 @@
 int strcasecmp(const char *s1, const char *s2);
 int strncasecmp(const char *s1, const char *s2, size_t n);
 
+#endif // _MSC_VER
+
 // empty functions
 inline int posix_openpt(int flag) { LLVM_BUILTIN_UNREACHABLE; }
 
diff --git a/lldb/source/Host/windows/FileSystem.cpp b/lldb/source/Host/windows/FileSystem.cpp
--- a/lldb/source/Host/windows/FileSystem.cpp
+++ b/lldb/source/Host/windows/FileSystem.cpp
@@ -12,6 +12,9 @@
 #include <sys/stat.h>
 #include <sys/types.h>
 
+// For _SH_*
+#include <share.h>
+
 #include "lldb/Host/FileSystem.h"
 #include "lldb/Host/windows/AutoHandle.h"
 #include "lldb/Host/windows/PosixApi.h"
diff --git a/lldb/source/Initialization/SystemInitializerCommon.cpp b/lldb/source/Initialization/SystemInitializerCommon.cpp
--- a/lldb/source/Initialization/SystemInitializerCommon.cpp
+++ b/lldb/source/Initialization/SystemInitializerCommon.cpp
@@ -25,6 +25,8 @@
 #if defined(_WIN32)
 #include "Plugins/Process/Windows/Common/ProcessWindowsLog.h"
 #include "lldb/Host/windows/windows.h"
+// for _CrtSetReportMode
+#include <crtdbg.h>
 #endif
 
 #include "llvm/Support/TargetSelect.h"
diff --git a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerPlatform.cpp b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerPlatform.cpp
--- a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerPlatform.cpp
+++ b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerPlatform.cpp
@@ -16,6 +16,11 @@
 #include <mutex>
 #include <sstream>
 
+#ifdef __MINGW32__
+// usleep
+#include <unistd.h>
+#endif
+
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/Threading.h"
 
diff --git a/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp b/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
--- a/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
+++ b/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
@@ -16,6 +16,10 @@
 #include <sys/socket.h>
 #include <unistd.h>
 #endif
+#ifdef __MINGW32__
+// usleep
+#include <unistd.h>
+#endif
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <time.h>
diff --git a/lldb/tools/driver/Platform.h b/lldb/tools/driver/Platform.h
--- a/lldb/tools/driver/Platform.h
+++ b/lldb/tools/driver/Platform.h
@@ -15,6 +15,10 @@
 #if defined(_MSC_VER)
 #include <signal.h>
 #endif
+#if defined(__MINGW32__)
+// pid_t
+#include <sys/types.h>
+#endif
 #include "lldb/Host/windows/windows.h"
 #include <inttypes.h>
 
diff --git a/lldb/tools/lldb-vscode/VSCode.cpp b/lldb/tools/lldb-vscode/VSCode.cpp
--- a/lldb/tools/lldb-vscode/VSCode.cpp
+++ b/lldb/tools/lldb-vscode/VSCode.cpp
@@ -16,7 +16,9 @@
 
 #if defined(_WIN32)
 #define NOMINMAX
+#ifndef __MINGW32__
 #include <Windows.h>
+#endif // __MINGW32__
 #include <fcntl.h>
 #include <io.h>
 #endif
diff --git a/lldb/tools/lldb-vscode/lldb-vscode.cpp b/lldb/tools/lldb-vscode/lldb-vscode.cpp
--- a/lldb/tools/lldb-vscode/lldb-vscode.cpp
+++ b/lldb/tools/lldb-vscode/lldb-vscode.cpp
@@ -50,7 +50,9 @@
 #include "VSCode.h"
 
 #if defined(_WIN32)
+#ifndef PATH_MAX
 #define PATH_MAX MAX_PATH
+#endif
 typedef int socklen_t;
 constexpr const char *dev_null_path = "nul";