C++ compiler flags removed (#338)

* be more verbose (#312)

* Improve and of ICMP messages on Windows.

When an ICMP message is received on Windows 10 for a UDP socket,
WSAECONNRESET is reported as an error. In this case, just read
again.

Thanks to nxrighthere for reporting the issue and helping to
nail it down.

This fixes #309.

* Fix broken links, Make URLs' protocols consistent (#315)

Two Links missed leading `http(s)://` and were broken.
All links to `tools.ietf.org` now consistently use https.

* Backport https://svnweb.freebsd.org/base?view=revision&revision=340783

* Improve input validation for the IPPROTO_SCTP level socket options
SCTP_CONNECT_X and SCTP_CONNECT_X_DELAYED.

* Allow sending on demand SCTP HEARTBEATS only in the ESTABLISHED state.

* Fix cross-build linux->mingw (#320)

* sync with master

* CMake: remove CXX flags
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 24c1352..b381c13 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -29,7 +29,7 @@
 # SUCH DAMAGE.
 #
 
-project(usrsctplib)
+project(usrsctplib C)
 cmake_minimum_required(VERSION 3.0)
 
 # Debug build type as default
@@ -160,76 +160,63 @@
 
 # SETTINGS FOR UNIX COMPILER
 if (CMAKE_C_COMPILER_ID MATCHES "Clang" OR CMAKE_C_COMPILER_ID MATCHES "AppleClang" OR CMAKE_C_COMPILER_ID MATCHES "GNU")
-	set(CMAKE_C_FLAGS   "${CMAKE_C_FLAGS}   -std=c99 -pedantic -Wall -Wextra")
-	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c99 -pedantic -Wall -Wextra")
+	set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -std=c99 -pedantic -Wall -Wextra")
 
 	check_c_compiler_flag(-Wfloat-equal has_wfloat_equal)
 	if (has_wfloat_equal)
-		set(CMAKE_C_FLAGS   "${CMAKE_C_FLAGS}   -Wfloat-equal")
-		set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wfloat-equal")
+		set(CMAKE_C_FLAGS  "${CMAKE_C_FLAGS} -Wfloat-equal")
 	endif ()
 
 	check_c_compiler_flag(-Wshadow has_wshadow)
 	if (has_wshadow)
-		set(CMAKE_C_FLAGS   "${CMAKE_C_FLAGS}   -Wshadow")
-		set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wshadow")
+		set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wshadow")
 	endif ()
 
 	check_c_compiler_flag(-Wpointer-arith has_wpointer_aritih)
 	if (has_wpointer_aritih)
-		set(CMAKE_C_FLAGS   "${CMAKE_C_FLAGS}   -Wpointer-arith")
-		set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wpointer-arith")
+		set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wpointer-arith")
 	endif ()
 
 	check_c_compiler_flag(-Wunreachable-code has_wunreachable_code)
 	if (has_wunreachable_code)
-		set(CMAKE_C_FLAGS   "${CMAKE_C_FLAGS}   -Wunreachable-code")
-		set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wunreachable-code")
+		set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wunreachable-code")
 	endif ()
 
 	check_c_compiler_flag(-Winit-self has_winit_self)
 	if (has_winit_self)
-		set(CMAKE_C_FLAGS   "${CMAKE_C_FLAGS}   -Winit-self")
-		set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Winit-self")
+		set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Winit-self")
 	endif ()
 
 	check_c_compiler_flag(-Wno-unused-function has_wno_unused_function)
 	if (has_wno_unused_function)
-		set(CMAKE_C_FLAGS   "${CMAKE_C_FLAGS}   -Wno-unused-function")
-		set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-unused-function")
+		set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wno-unused-function")
 	endif ()
 
 	check_c_compiler_flag(-Wno-unused-parameter has_wno_unused_parameter)
 	if (has_wno_unused_parameter)
-		set(CMAKE_C_FLAGS   "${CMAKE_C_FLAGS}   -Wno-unused-parameter")
-		set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-unused-parameter")
+		set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wno-unused-parameter")
 	endif ()
 
 	check_c_compiler_flag(-Wno-unreachable-code has_wno_unreachable_code)
 	if (has_wno_unreachable_code)
-		set(CMAKE_C_FLAGS   "${CMAKE_C_FLAGS}   -Wno-unreachable-code")
-		set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-unreachable-code")
+		set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wno-unreachable-code")
 	endif ()
 
 	check_c_compiler_flag(-Wstrict-prototypes has_wstrict_prototypes)
 	if (has_wstrict_prototypes)
-		set(CMAKE_C_FLAGS   "${CMAKE_C_FLAGS}   -Wstrict-prototypes")
-		set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wstrict-prototypes")
+		set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wstrict-prototypes")
 	endif ()
 
 	if (sctp_werror)
-		set(CMAKE_C_FLAGS   "${CMAKE_C_FLAGS}   -Werror")
-		set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Werror")
+		set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Werror")
 	endif ()
 
 	if (sctp_sanitizer_address)
-		set(CMAKE_C_FLAGS   "${CMAKE_C_FLAGS}   -fsanitize=address -fno-omit-frame-pointer -g")
-		set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fsanitize=address -fno-omit-frame-pointer -g")
+		set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fsanitize=address -fno-omit-frame-pointer -g")
 	endif ()
 
 	if (sctp_sanitizer_memory)
-		set(CMAKE_C_FLAGS   "${CMAKE_C_FLAGS}   -fsanitize=memory -fno-omit-frame-pointer -g -fsanitize-memory-track-origins")
-		set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fsanitize=memory -fno-omit-frame-pointer -g -fsanitize-memory-track-origins")
+		set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fsanitize=memory -fno-omit-frame-pointer -g -fsanitize-memory-track-origins")
 	endif ()
 endif ()
 
diff --git a/programs/CMakeLists.txt b/programs/CMakeLists.txt
index 8e37266..b99d181 100644
--- a/programs/CMakeLists.txt
+++ b/programs/CMakeLists.txt
@@ -66,7 +66,6 @@
 	if (CMAKE_C_COMPILER_ID MATCHES "GNU")
 		message(STATUS "MSYS / MINGW + GCC")
 		set(CMAKE_C_FLAGS   "${CMAKE_C_FLAGS}   -Wno-format")
-		set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-format")
 	endif ()
 endif ()
 
diff --git a/usrsctplib/CMakeLists.txt b/usrsctplib/CMakeLists.txt
index 5e86670..6aa6b02 100644
--- a/usrsctplib/CMakeLists.txt
+++ b/usrsctplib/CMakeLists.txt
@@ -60,14 +60,12 @@
 if (CMAKE_SYSTEM_NAME MATCHES "FreeBSD")
 	add_definitions(-U__FreeBSD__)
 	set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS}     -Wno-address-of-packed-member")
-	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-address-of-packed-member")
 endif ()
 
 if (CMAKE_SYSTEM_NAME MATCHES "Darwin")
 	add_definitions(-U__APPLE__)
 	add_definitions(-D__APPLE_USE_RFC_2292)
 	set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS}     -Wno-address-of-packed-member -Wno-deprecated-declarations")
-	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-address-of-packed-member -Wno-deprecated-declarations")
 endif ()
 
 if (CMAKE_SYSTEM_NAME MATCHES "DragonFly")