diff --git a/src/openrct2/Version.h b/src/openrct2/Version.h
index 009024a232..f0630a185f 100644
--- a/src/openrct2/Version.h
+++ b/src/openrct2/Version.h
@@ -38,16 +38,16 @@
 #endif
 
 // Platform
-#ifdef __WINDOWS__
+#ifdef _WIN32
     #define OPENRCT2_PLATFORM       "Windows"
 #endif
-#ifdef __LINUX__
+#ifdef __linux__
     #define OPENRCT2_PLATFORM       "Linux"
 #endif
-#ifdef __MACOSX__
+#if (defined(__APPLE__) && defined(__MACH__))
     #define OPENRCT2_PLATFORM       "macOS"
 #endif
-#ifdef __FREEBSD__
+#ifdef __FreeBSD__
     #define OPENRCT2_PLATFORM       "FreeBSD"
 #endif
 #ifndef OPENRCT2_PLATFORM
diff --git a/src/openrct2/audio/audio.cpp b/src/openrct2/audio/audio.cpp
index e26e1750e4..66eb49925a 100644
--- a/src/openrct2/audio/audio.cpp
+++ b/src/openrct2/audio/audio.cpp
@@ -176,7 +176,7 @@ void audio_populate_devices()
         }
     }
 
-#ifndef __LINUX__
+#ifndef __linux__
     // The first device is always system default on Windows and macOS
     std::string defaultDevice = language_get_string(STR_OPTIONS_SOUND_VALUE_DEFAULT);
     devices.insert(devices.begin(), defaultDevice);
diff --git a/src/openrct2/cmdline/CommandLine.cpp b/src/openrct2/cmdline/CommandLine.cpp
index 918da0d23c..df1f8a59e1 100644
--- a/src/openrct2/cmdline/CommandLine.cpp
+++ b/src/openrct2/cmdline/CommandLine.cpp
@@ -519,7 +519,7 @@ namespace CommandLine
 
     static bool HandleSpecialArgument(const char * argument)
     {
-#ifdef __MACOSX__
+#ifdef __APPLE__
         if (String::Equals(argument, "-NSDocumentRevisionsDebugMode"))
         {
             return true;
diff --git a/src/openrct2/cmdline/RootCommands.cpp b/src/openrct2/cmdline/RootCommands.cpp
index 2aa9243f17..e1a828686b 100644
--- a/src/openrct2/cmdline/RootCommands.cpp
+++ b/src/openrct2/cmdline/RootCommands.cpp
@@ -94,7 +94,7 @@ static exitcode_t HandleCommandJoin(CommandLineArgEnumerator * enumerator);
 static exitcode_t HandleCommandSetRCT2(CommandLineArgEnumerator * enumerator);
 static exitcode_t HandleCommandScanObjects(CommandLineArgEnumerator * enumerator);
 
-#if defined(__WINDOWS__) && !defined(__MINGW32__)
+#if defined(_WIN32) && !defined(__MINGW32__)
 
 static bool _removeShell = false;
 
@@ -131,7 +131,7 @@ const CommandLineCommand CommandLine::RootCommands[]
     DefineCommand("scan-objects", "<path>",             StandardOptions, HandleCommandScanObjects),
     DefineCommand("handle-uri", "openrct2://.../",      StandardOptions, CommandLine::HandleCommandUri),
 
-#if defined(__WINDOWS__) && !defined(__MINGW32__)
+#if defined(_WIN32) && !defined(__MINGW32__)
     DefineCommand("register-shell", "", RegisterShellOptions, HandleCommandRegisterShell),
 #endif
 
@@ -400,7 +400,7 @@ static exitcode_t HandleCommandScanObjects(CommandLineArgEnumerator * enumerator
     return EXITCODE_OK;
 }
 
-#if defined(__WINDOWS__) && !defined(__MINGW32__)
+#if defined(_WIN32) && !defined(__MINGW32__)
 static exitcode_t HandleCommandRegisterShell(CommandLineArgEnumerator * enumerator)
 {
     exitcode_t result = CommandLine::HandleCommandDefault();
@@ -419,7 +419,7 @@ static exitcode_t HandleCommandRegisterShell(CommandLineArgEnumerator * enumerat
     }
     return EXITCODE_OK;
 }
-#endif // defined(__WINDOWS__) && !defined(__MINGW32__)
+#endif // defined(_WIN32) && !defined(__MINGW32__)
 
 static void PrintAbout()
 {
diff --git a/src/openrct2/common.h b/src/openrct2/common.h
index 98c034b417..84863348dd 100644
--- a/src/openrct2/common.h
+++ b/src/openrct2/common.h
@@ -17,8 +17,6 @@
 #ifndef _COMMON_H_
 #define _COMMON_H_
 
-#include <SDL_platform.h>
-
 #ifndef _USE_MATH_DEFINES
 #define _USE_MATH_DEFINES
 #endif
@@ -52,7 +50,7 @@ typedef uint64_t uint64;
 typedef char utf8;
 typedef utf8* utf8string;
 typedef const utf8* const_utf8string;
-#ifdef __WINDOWS__
+#ifdef _WIN32
 typedef wchar_t utf16;
 typedef utf16* utf16string;
 #endif
diff --git a/src/openrct2/core/FileScanner.cpp b/src/openrct2/core/FileScanner.cpp
index 1d97715537..f2efeb689a 100644
--- a/src/openrct2/core/FileScanner.cpp
+++ b/src/openrct2/core/FileScanner.cpp
@@ -16,7 +16,7 @@
 
 #include "../common.h"
 
-#ifdef __WINDOWS__
+#ifdef _WIN32
     #define WIN32_LEAN_AND_MEAN
     #include <windows.h>
 #endif
@@ -26,7 +26,7 @@
     #include <sys/types.h>
     #include <sys/stat.h>
     #include <unistd.h>
-#elif defined(__WINDOWS__)
+#elif defined(_WIN32)
     extern "C" {
         // Windows needs this for widechar <-> utf8 conversion utils
         #include "../localisation/language.h"
@@ -227,7 +227,7 @@ protected:
 
 };
 
-#ifdef __WINDOWS__
+#ifdef _WIN32
 
 class FileScannerWindows final : public FileScannerBase
 {
@@ -286,7 +286,7 @@ private:
     }
 };
 
-#endif // __WINDOWS__
+#endif // _WIN32
 
 #if defined(__unix__) || (defined(__APPLE__) && defined(__MACH__))
 
@@ -362,7 +362,7 @@ private:
 
 IFileScanner * Path::ScanDirectory(const std::string &pattern, bool recurse)
 {
-#ifdef __WINDOWS__
+#ifdef _WIN32
     return new FileScannerWindows(pattern, recurse);
 #elif defined(__unix__) || (defined(__APPLE__) && defined(__MACH__))
     return new FileScannerUnix(pattern, recurse);
diff --git a/src/openrct2/core/Guard.cpp b/src/openrct2/core/Guard.cpp
index bfddbd121e..ffb8546740 100644
--- a/src/openrct2/core/Guard.cpp
+++ b/src/openrct2/core/Guard.cpp
@@ -20,7 +20,7 @@
 
 #include "../common.h"
 
-#ifdef __WINDOWS__
+#ifdef _WIN32
 #define WIN32_LEAN_AND_MEAN
 #include <windows.h>
 #undef GetMessage
@@ -50,14 +50,14 @@ namespace Guard
 
     // The default behaviour when an assertion is raised.
     static ASSERT_BEHAVIOUR _assertBehaviour =
-#ifdef __WINDOWS__
+#ifdef _WIN32
         ASSERT_BEHAVIOUR::MESSAGE_BOX
 #else
         ASSERT_BEHAVIOUR::CASSERT
 #endif
         ;
 
-#ifdef __WINDOWS__
+#ifdef _WIN32
     static void GetAssertMessage(char * buffer, size_t bufferSize, const char * formattedMessage);
     static void ForceCrash();
 #endif
@@ -107,7 +107,7 @@ namespace Guard
         case ASSERT_BEHAVIOUR::CASSERT:
             assert(false);
             break;
-#ifdef __WINDOWS__
+#ifdef _WIN32
         case ASSERT_BEHAVIOUR::MESSAGE_BOX:
         {
             // Show message box if we are not building for testing
@@ -137,7 +137,7 @@ namespace Guard
         Assert_VA(false, message, args);
     }
 
-#ifdef __WINDOWS__
+#ifdef _WIN32
     static void GetAssertMessage(char * buffer, size_t bufferSize, const char * formattedMessage)
     {
         String::Set(buffer, bufferSize, ASSERTION_MESSAGE);
diff --git a/src/openrct2/core/Path.cpp b/src/openrct2/core/Path.cpp
index 81c299686f..17149dc9b5 100644
--- a/src/openrct2/core/Path.cpp
+++ b/src/openrct2/core/Path.cpp
@@ -88,7 +88,7 @@ namespace Path
             {
                 lastPathSeperator = ch;
             }
-#ifdef __WINDOWS__
+#ifdef _WIN32
             // Windows also allows forward slashes in paths
             else if (*ch == '/')
             {
@@ -174,7 +174,7 @@ namespace Path
 
     utf8 * GetAbsolute(utf8 *buffer, size_t bufferSize, const utf8 * relativePath)
     {
-#ifdef __WINDOWS__
+#ifdef _WIN32
         wchar_t * relativePathW = utf8_to_widechar(relativePath);
         wchar_t   absolutePathW[MAX_PATH];
         DWORD length = GetFullPathNameW(relativePathW, (DWORD)Util::CountOf(absolutePathW), absolutePathW, NULL);
@@ -213,7 +213,7 @@ namespace Path
     bool Equals(const utf8 * a, const utf8 * b)
     {
         bool ignoreCase = false;
-#ifdef __WINDOWS__
+#ifdef _WIN32
         ignoreCase = true;
 #endif
         return String::Equals(a, b, ignoreCase);
diff --git a/src/openrct2/drawing/NewDrawing.cpp b/src/openrct2/drawing/NewDrawing.cpp
index 63edba8953..83d0bdfdca 100644
--- a/src/openrct2/drawing/NewDrawing.cpp
+++ b/src/openrct2/drawing/NewDrawing.cpp
@@ -62,7 +62,7 @@ extern "C"
         // Linux requires a restart. This could be improved in the future by recreating the window,
         // https://github.com/OpenRCT2/OpenRCT2/issues/2015
         bool requiresRestart = true;
-#ifdef __WINDOWS__
+#ifdef _WIN32
         if (dstEngine != DRAWING_ENGINE_OPENGL)
         {
             // Windows is apparently able to switch to hardware rendering on the fly although
diff --git a/src/openrct2/localisation/localisation.c b/src/openrct2/localisation/localisation.c
index 369f24f83a..903bb18ee1 100644
--- a/src/openrct2/localisation/localisation.c
+++ b/src/openrct2/localisation/localisation.c
@@ -18,12 +18,12 @@
 
 #include <ctype.h>
 
-#ifdef __WINDOWS__
+#ifdef _WIN32
 #include <windows.h>
 #else
 #include <iconv.h>
 #include <errno.h>
-#endif // __WINDOWS__
+#endif // _WIN32
 
 #include "../config/Config.h"
 #include "../game.h"
@@ -1328,7 +1328,7 @@ utf8 *win1252_to_utf8_alloc(const char *src, size_t srcMaxSize)
 
 sint32 win1252_to_utf8(utf8string dst, const char *src, size_t srcLength, size_t maxBufferLength)
 {
-#ifdef __WINDOWS__
+#ifdef _WIN32
     utf16 stackBuffer[256];
     utf16 *heapBuffer = NULL;
     utf16 *intermediateBuffer = stackBuffer;
@@ -1396,7 +1396,7 @@ sint32 win1252_to_utf8(utf8string dst, const char *src, size_t srcLength, size_t
     //log_warning("converted %s of size %d, %d", dst, byte_diff, strlen(dst));
     sint32 result = byte_diff;
     free(buffer_orig);
-#endif // __WINDOWS__
+#endif // _WIN32
 
     return result;
 }
diff --git a/src/openrct2/network/TcpSocket.cpp b/src/openrct2/network/TcpSocket.cpp
index dcc17b9eeb..95b2986d51 100644
--- a/src/openrct2/network/TcpSocket.cpp
+++ b/src/openrct2/network/TcpSocket.cpp
@@ -54,7 +54,7 @@
     #define LAST_SOCKET_ERROR() errno
     #define closesocket close
     #define ioctlsocket ioctl
-    #if defined(__LINUX__)
+    #if defined(__linux__)
         #define FLAG_NO_PIPE MSG_NOSIGNAL
     #else
         #define FLAG_NO_PIPE 0
@@ -457,7 +457,7 @@ private:
 
     static bool SetNonBlocking(SOCKET socket, bool on)
     {
-#ifdef __WINDOWS__
+#ifdef _WIN32
         u_long nonBlocking = on;
         return ioctlsocket(socket, FIONBIO, &nonBlocking) == 0;
 #else
@@ -479,7 +479,7 @@ ITcpSocket * CreateTcpSocket()
 
 bool InitialiseWSA()
 {
-#ifdef __WINDOWS__
+#ifdef _WIN32
     if (!_wsaInitialised)
     {
         log_verbose("Initialising WSA");
@@ -499,7 +499,7 @@ bool InitialiseWSA()
 
 void DisposeWSA()
 {
-#ifdef __WINDOWS__
+#ifdef _WIN32
     if (_wsaInitialised)
     {
         WSACleanup();
diff --git a/src/openrct2/network/http.cpp b/src/openrct2/network/http.cpp
index 74c0b1a035..f5c015cf2a 100644
--- a/src/openrct2/network/http.cpp
+++ b/src/openrct2/network/http.cpp
@@ -33,7 +33,7 @@ void http_dispose() { }
 #include "../core/String.hpp"
 #include "../Version.h"
 
-#ifdef __WINDOWS__
+#ifdef _WIN32
     // cURL includes windows.h, but we don't need all of it.
     #define WIN32_LEAN_AND_MEAN
 #endif
diff --git a/src/openrct2/platform/linux.c b/src/openrct2/platform/linux.c
index 1019439a02..e8d5b0298b 100644
--- a/src/openrct2/platform/linux.c
+++ b/src/openrct2/platform/linux.c
@@ -18,7 +18,7 @@
 
 // Despite the name, this file contains support for more OSs besides Linux, provided the necessary ifdefs remain small.
 // Otherwise, they should be spun off into their own files.
-#if defined(__LINUX__) || defined(__FREEBSD__)
+#if defined(__linux__) || defined(__FREEBSD__)
 
 #ifdef __FREEBSD__
 #include <sys/sysctl.h>
@@ -42,7 +42,7 @@
 void platform_get_exe_path(utf8 *outPath, size_t outSize)
 {
     char exePath[MAX_PATH];
-#ifdef __LINUX__
+#ifdef __linux__
     ssize_t bytesRead;
     bytesRead = readlink("/proc/self/exe", exePath, MAX_PATH);
     if (bytesRead == -1) {
diff --git a/src/openrct2/platform/platform.h b/src/openrct2/platform/platform.h
index dea6d15c8b..88646e3058 100644
--- a/src/openrct2/platform/platform.h
+++ b/src/openrct2/platform/platform.h
@@ -26,7 +26,7 @@ typedef struct rct2_install_info rct2_install_info;
 #define MAX_PATH 260
 #endif
 
-#ifdef __MACOSX__
+#ifdef __APPLE__
 #define KEYBOARD_PRIMARY_MODIFIER KMOD_GUI
 #else
 #define KEYBOARD_PRIMARY_MODIFIER KMOD_CTRL
@@ -36,7 +36,7 @@ typedef struct rct2_install_info rct2_install_info;
 
 #define TOUCH_DOUBLE_TIMEOUT 300
 
-#ifdef __WINDOWS__
+#ifdef _WIN32
 #define PATH_SEPARATOR "\\"
 #define PLATFORM_NEWLINE "\r\n"
 #else
@@ -48,7 +48,7 @@ typedef struct rct2_install_info rct2_install_info;
 #define CTRL 0x200
 #define ALT 0x400
 #define CMD 0x800
-#ifdef __MACOSX__
+#ifdef __APPLE__
     #define PLATFORM_MODIFIER CMD
 #else
     #define PLATFORM_MODIFIER CTRL
@@ -155,7 +155,7 @@ datetime64 platform_get_datetime_now_utc();
 void core_init();
 
 // Windows specific definitions
-#ifdef __WINDOWS__
+#ifdef _WIN32
     #ifndef WIN32_LEAN_AND_MEAN
         #define WIN32_LEAN_AND_MEAN
     #endif
@@ -169,14 +169,14 @@ void core_init();
     // This function cannot be marked as 'static', even though it may seem to be,
     // as it requires external linkage, which 'static' prevents
     __declspec(dllexport) sint32 StartOpenRCT(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, sint32 nCmdShow);
-#endif // __WINDOWS__
+#endif // _WIN32
 
-#if defined(__LINUX__) || defined(__MACOSX__) || defined(__FREEBSD__)
+#if defined(__unix__) || (defined(__APPLE__) && defined(__MACH__)) || defined(__FreeBSD__)
     void platform_posix_sub_user_data_path(char *buffer, size_t size, const char *homedir);
     void platform_posix_sub_resolve_openrct_data_path(utf8 *out, size_t size);
 #endif
 
-#ifdef __MACOSX__
+#if defined(__APPLE__) && defined(__MACH__)
     void macos_disallow_automatic_window_tabbing();
     utf8* macos_str_decomp_to_precomp();
 #endif
diff --git a/src/openrct2/platform/posix.c b/src/openrct2/platform/posix.c
index 5ade19fe79..8f15b43b33 100644
--- a/src/openrct2/platform/posix.c
+++ b/src/openrct2/platform/posix.c
@@ -374,7 +374,7 @@ sint32 platform_enumerate_files_begin(const utf8 *pattern)
 // macOS uses decomposed Unicode strings (e.g. an 'e' and a combining accent) in filenames
 // This causes problems with the sprite font, as the font only contains precomposed characters
 // The block below converts all filename strings to their precomposed form, preventing mojibake
-#ifdef __MACOSX__
+#ifdef __APPLE__
                 utf8* precomp_path = macos_str_decomp_to_precomp(paths[idx]);
                 size_t precomp_len = sizeof(utf8) * min(MAX_PATH, strnlen(precomp_path, MAX_PATH) + 2);
                 paths[idx] = malloc(precomp_len);
diff --git a/src/openrct2/platform/windows.c b/src/openrct2/platform/windows.c
index ac4c03d566..79c916d29f 100644
--- a/src/openrct2/platform/windows.c
+++ b/src/openrct2/platform/windows.c
@@ -22,7 +22,7 @@
 
 #include "../common.h"
 
-#ifdef __WINDOWS__
+#ifdef _WIN32
 
 #include <windows.h>
 #include <lmcons.h>
diff --git a/src/openrct2/rct2/hook.c b/src/openrct2/rct2/hook.c
index 7201ceddb7..b0b9068a01 100644
--- a/src/openrct2/rct2/hook.c
+++ b/src/openrct2/rct2/hook.c
@@ -18,11 +18,11 @@
 
 #ifndef NO_RCT2
 
-#ifdef __WINDOWS__
+#ifdef _WIN32
     #include <windows.h>
 #else
     #include <sys/mman.h>
-#endif // __WINDOWS__
+#endif // _WIN32
 
 #include "../platform/platform.h"
 #include "hook.h"
@@ -154,19 +154,19 @@ static void hookfunc(uintptr_t address, uintptr_t hookAddress, sint32 stacksize)
 
     data[i++] = 0xC3; // retn
 
-#ifdef __WINDOWS__
+#ifdef _WIN32
     WriteProcessMemory(GetCurrentProcess(), (LPVOID)address, data, i, 0);
 #else
     // We own the pages with PROT_WRITE | PROT_EXEC, we can simply just memcpy the data
     memcpy((void *)address, data, i);
-#endif // __WINDOWS__
+#endif // _WIN32
 }
 
 void addhook(uintptr_t address, hook_function *function)
 {
     if (!_hookTableAddress) {
         size_t size = _maxHooks * HOOK_BYTE_COUNT;
-#ifdef __WINDOWS__
+#ifdef _WIN32
         _hookTableAddress = VirtualAllocEx(GetCurrentProcess(), NULL, size, MEM_COMMIT, PAGE_EXECUTE_READWRITE);
 #else
         _hookTableAddress = mmap(NULL, size, PROT_EXEC | PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
@@ -175,7 +175,7 @@ void addhook(uintptr_t address, hook_function *function)
             perror("mmap");
             exit(1);
         }
-#endif // __WINDOWS__
+#endif // _WIN32
     }
     if (_hookTableOffset > _maxHooks) {
         return;
@@ -189,7 +189,7 @@ void addhook(uintptr_t address, hook_function *function)
     i += 4;
 
     data[i++] = 0xC3; // retn
-#ifdef __WINDOWS__
+#ifdef _WIN32
     WriteProcessMemory(GetCurrentProcess(), (LPVOID)address, data, i, 0);
 #else
     // We own the pages with PROT_WRITE | PROT_EXEC, we can simply just memcpy the data
@@ -206,7 +206,7 @@ void addhook(uintptr_t address, hook_function *function)
     {
         perror("mprotect");
     }
-#endif // __WINDOWS__
+#endif // _WIN32
     hookfunc(hookaddress, (uintptr_t)function, 0);
     _hookTableOffset++;
 }
diff --git a/src/openrct2/rct2/interop.c b/src/openrct2/rct2/interop.c
index 87a3cf0c0d..fffd685a0a 100644
--- a/src/openrct2/rct2/interop.c
+++ b/src/openrct2/rct2/interop.c
@@ -18,19 +18,19 @@
 
 #include "../common.h"
 
-#if defined(__WINDOWS__)
+#if defined(_WIN32)
     #define WIN32_LEAN_AND_MEAN
     #include <windows.h>
 #endif
 
-#if defined(__unix__) || defined(__MACOSX__)
+#if defined(__unix__) || defined(__APPLE__)
     #include <sys/mman.h>
     #include <errno.h>
     #include <fcntl.h>
     #include <sys/types.h>
     #include <sys/stat.h>
     #include <unistd.h>
-#endif // defined(__unix__) || defined(__MACOSX__)
+#endif // defined(__unix__) || defined(__APPLE__)
 
 #include "../OpenRCT2.h"
 #include "../util/sawyercoding.h"
@@ -39,7 +39,7 @@
 #include "hook.h"
 #include "interop.h"
 
-#if defined(USE_MMAP) && (defined(__unix__) || defined(__MACOSX__)) && !defined(NO_RCT2)
+#if defined(USE_MMAP) && (defined(__unix__) || defined(__APPLE__)) && !defined(NO_RCT2)
     static sint32 fdData = -1;
 #endif
 #if !defined(NO_RCT2)
@@ -68,7 +68,7 @@ bool rct2_interop_setup_segment()
 #if !defined(NO_RCT2)
     UNUSED(segments);
 #endif
-#if defined(USE_MMAP) && (defined(__unix__) || defined(__MACOSX__)) && !defined(NO_RCT2)
+#if defined(USE_MMAP) && (defined(__unix__) || defined(__APPLE__)) && !defined(NO_RCT2)
     #define RDATA_OFFSET 0x004A4000
     #define DATASEG_OFFSET 0x005E2000
 
@@ -116,7 +116,7 @@ bool rct2_interop_setup_segment()
         perror("mmap");
         return false;
     }
-#endif // defined(USE_MMAP) && (defined(__unix__) || defined(__MACOSX__))
+#endif // defined(USE_MMAP) && (defined(__unix__) || defined(__APPLE__))
 
 #if defined(__unix__) && !defined(NO_RCT2)
     sint32 pageSize = getpagesize();
@@ -128,7 +128,7 @@ bool rct2_interop_setup_segment()
     if (err != 0)
     {
         err = errno;
-#ifdef __LINUX__
+#ifdef __linux__
         // On Linux ENOMEM means all requested range is unmapped
         if (err != ENOMEM)
         {
@@ -138,7 +138,7 @@ bool rct2_interop_setup_segment()
 #else
         pagesMissing = true;
         perror("mincore");
-#endif // __LINUX__
+#endif // __linux__
     } else {
         for (sint32 i = 0; i < numPages; i++)
         {
@@ -172,7 +172,7 @@ bool rct2_interop_setup_segment()
     }
 #endif // defined(__unix__)
 
-#if defined(USE_MMAP) && defined(__WINDOWS__)
+#if defined(USE_MMAP) && defined(_WIN32)
     segments = VirtualAlloc((void *)(GOOD_PLACE_FOR_DATA_SEGMENT), len, MEM_COMMIT | MEM_RESERVE, PAGE_READWRITE);
     if ((uintptr_t)segments != GOOD_PLACE_FOR_DATA_SEGMENT) {
         log_error("VirtualAlloc, segments = %p, GetLastError = 0x%x", segments, GetLastError());
@@ -195,7 +195,7 @@ bool rct2_interop_setup_segment()
         return false;
     }
     fclose(file);
-#endif // defined(USE_MMAP) && defined(__WINDOWS__)
+#endif // defined(USE_MMAP) && defined(_WIN32)
 
 #if !defined(NO_RCT2) && defined(USE_MMAP)
     // Check that the expected data is at various addresses.
@@ -224,7 +224,7 @@ void rct2_interop_setup_hooks()
 
 void rct2_interop_dispose()
 {
-#if defined(USE_MMAP) && (defined(__unix__) || defined(__MACOSX__)) && !defined(NO_RCT2)
+#if defined(USE_MMAP) && (defined(__unix__) || defined(__APPLE__)) && !defined(NO_RCT2)
     munmap(segments, 12079104);
     close(fdData);
 #endif
diff --git a/src/openrct2/windows/options.c b/src/openrct2/windows/options.c
index b7bade9dc8..911c619625 100644
--- a/src/openrct2/windows/options.c
+++ b/src/openrct2/windows/options.c
@@ -1884,11 +1884,11 @@ static void window_options_paint(rct_window *w, rct_drawpixelinfo *dpi)
             audioDeviceStringId = STR_SOUND_NONE;
         } else {
             audioDeviceStringId = STR_STRING;
-#ifndef __LINUX__
+#ifndef __linux__
             if (gAudioCurrentDevice == 0) {
                 audioDeviceStringId = STR_OPTIONS_SOUND_VALUE_DEFAULT;
             }
-#endif // __LINUX__
+#endif // __linux__
             if (audioDeviceStringId == STR_STRING) {
                 audioDeviceName = gAudioDevices[gAudioCurrentDevice].name;
             }