[win32] use boost filesystem for gcc builds

Signed-off-by: r4sas <r4sas@i2pmail.org>

Makefile.mingw

@@ -7,7 +7,7 @@ CXXFLAGS := $(CXX_DEBUG) -fPIC -msse
 INCFLAGS := -I$(DAEMON_SRC_DIR) -IWin32
 LDFLAGS := ${LD_DEBUG} -static -fPIC -msse
 
-NEEDED_CXXFLAGS += -std=c++17
+NEEDED_CXXFLAGS += -std=c++20
 DEFINES += -DWIN32_LEAN_AND_MEAN
 
 # UPNP Support
@@ -16,7 +16,12 @@ ifeq ($(USE_UPNP),yes)
 	LDLIBS = -lminiupnpc
 endif
 
+ifeq ($(USE_WINXP_FLAGS), yes)
+	DEFINES += -DWINVER=0x0501 -D_WIN32_WINNT=0x0501
+endif
+
 LDLIBS += \
+	$(MINGW_PREFIX)/lib/libboost_filesystem-mt.a \
 	$(MINGW_PREFIX)/lib/libboost_program_options-mt.a \
 	$(MINGW_PREFIX)/lib/libssl.a \
 	$(MINGW_PREFIX)/lib/libcrypto.a \
@@ -37,10 +42,6 @@ ifeq ($(USE_WIN32_APP), yes)
 	DAEMON_OBJS += $(patsubst %.rc,obj/%.o,$(DAEMON_RC))
 endif
 
-ifeq ($(USE_WINXP_FLAGS), yes)
-	DEFINES += -DWINVER=0x0501 -D_WIN32_WINNT=0x0501
-endif
-
 ifeq ($(USE_AESNI),yes)
 	NEEDED_CXXFLAGS += -maes
 	LDFLAGS += -maes

Win32/Win32NetState.cpp

@@ -1,5 +1,5 @@
 /*
-* Copyright (c) 2013-2020, The PurpleI2P Project
+* Copyright (c) 2013-2024, The PurpleI2P Project
 *
 * This file is part of Purple i2pd project and licensed under BSD3
 *

Win32/Win32NetState.h

@@ -1,5 +1,5 @@
 /*
-* Copyright (c) 2013-2020, The PurpleI2P Project
+* Copyright (c) 2013-2024, The PurpleI2P Project
 *
 * This file is part of Purple i2pd project and licensed under BSD3
 *

libi2pd/FS.h

@@ -16,7 +16,9 @@
 #include <functional>
 
 #ifndef STD_FILESYSTEM
-#	if (!TARGET_OS_SIMULATOR && __has_include(<filesystem>)) // supports std::filesystem
+#	if (_WIN32 && __GNUG__) // MinGW GCC somehow incorrectly converts paths
+#		define STD_FILESYSTEM 0
+#	elif (!TARGET_OS_SIMULATOR && __has_include(<filesystem>)) // supports std::filesystem
 #		define STD_FILESYSTEM 1
 #	else
 #		define STD_FILESYSTEM 0