Add dockcross for C++ x86 cross compilation. (#8)

* Add dockcross for C++ x86 cross compilation.

* Add dockcross containers for all cross compilation targets

.gitignore

@@ -215,4 +215,6 @@ test/run_real_world_samples.sh
 
 src/cwe_checker.plugin
 
+test/artificial_samples/dockcross*
+
 .#*

test/artificial_samples/install_cross_compilers_ubuntu_18.04.sh

 #!/bin/bash
 echo "Installing cross compiler for ARM architecture."
-sudo apt install -y gcc-multilib-arm-linux-gnueabi g++-arm-linux-gnueabi
+sudo docker pull dockcross/linux-arm64
+sudo docker run -rm dockcross/linux-arm64 > ./dockcross-linux-arm64
+chmod +x ./dockcross-linux-arm64
 echo "Installing cross compiler for MIPS architecture."
-sudo apt install -y gcc-multilib-mips-linux-gnu g++-7-mips-linux-gnu
+sudo docker pull dockcross/linux-mips
+sudo docker run -rm dockcross/linux-mips > ./dockcross-linux-mips
+chmod +x ./dockcross-linux-mips
 echo "Installing cross compiler for PPC architecture."
-sudo apt install -y gcc-multilib-powerpc-linux-gnu g++-7-powerpc-linux-gnu
+sudo docker pull dockcross/linux-ppc64le
+sudo docker run -rm dockcross/linux-ppc64le > ./dockcross-linux-ppc64le
+chmod +x ./dockcross-linux-ppc64le
+echo "Installing dockcross image for x86 C++ cross-compiler"
+sudo docker pull dockcross/linux-x86
+sudo docker run -rm dockcross/linux-x86 > ./dockcross-linux-x86
+chmod +x ./dockcross-linux-x86
 echo "Done."

test/artificial_samples/makefile

 CC_x64=gcc
-CC_X86=gcc
-CC_ARM=arm-linux-gnueabi-gcc-7
-CC_MIPS=mips-linux-gnu-gcc-7
-CC_PPC=powerpc-linux-gnu-gcc-7
+CC_X86=./dockcross-linux-x86 gcc
+CC_ARM=./dockcross-linux-arm64 arm-linux-gnueabi-gcc-7
+CC_MIPS=./dockcross-linux-mips mips-linux-gnu-gcc-7
+CC_PPC=./dockcross-linux-ppc64le powerpc-linux-gnu-gcc-7
 
 CPP_x64=g++
-CPP_X86=g++
-CPP_ARM=arm-linux-gnueabi-g++-7
-CPP_MIPS=mips-linux-gnu-g++-7
-CPP_PPC=powerpc-linux-gnu-g++-7
+CPP_X86=./dockcross-linux-x86 g++
+CPP_ARM=./dockcross-linux-arm64 arm-linux-gnueabi-g++-7
+CPP_MIPS=./dockcross-linux-mips mips-linux-gnu-g++-7
+CPP_PPC=./dockcross-linux-ppc64le powerpc-linux-gnu-g++-7
 
 CFLAGS_X64=-O0 -g -fno-stack-protector
 CFLAGS_X86=-O0 -g -m32 -fno-stack-protector
@@ -88,8 +88,7 @@ endef
 define compile_all_cpp
 	$(shell mkdir -p "build")
 	$(call compile_x64_cpp,$(1))
-# building fails
-# (call compile_x86_cpp,$(1))
+	$(call compile_x86_cpp,$(1))
 	$(call compile_arm_cpp,$(1))
 	$(call compile_mips_cpp,$(1))
 	$(call compile_ppc_cpp,$(1))