kernel: add c++ support

tools/make/gcc-host.mk

@@ -1,7 +1,9 @@
 LD  := gcc
 CC  := gcc
+CXX := g++
 ASM := gcc
 
 CFLAGS   := -Wall -Werror -pedantic
+CXXFLAGS := $(CFLAGS)
 ASMFLAGS := $(CFLAGS)
 LDFLAGS  := -O2

tools/make/generate_compile_commands.py

@@ -5,7 +5,7 @@ import os
 
 
 def is_source_file(filepath):
-    return filepath.endswith('.c') or filepath.endswith('.h') or filepath.endswith('.S')
+    return filepath.endswith('.c') or filepath.endswith('.cpp') or filepath.endswith('.h') or filepath.endswith('.S')
 
 dir_stack = []
 rootdir = os.getcwd()
@@ -30,7 +30,7 @@ for line in make_output_lines:
         dir_stack.pop()
         continue;
 
-    if 'gcc' not in line_parts[0]:
+    if 'gcc' not in line_parts[0] and 'g++' not in line_parts[0]:
         continue
 
     src_file = ''