diff --git a/Makefile b/Makefile
index 07f43581..1b13d2e0 100644
--- a/Makefile
+++ b/Makefile
@@ -104,7 +104,7 @@ default: ispc
 
 depend: llvm_check $(CXX_SRC) $(HEADERS)
 	@echo Updating dependencies
-	@gcc -MM $(CXXFLAGS) $(CXX_SRC) | sed 's_^\([a-z]\)_objs/\1_g' > depend
+	@$(CXX) -MM $(CXXFLAGS) $(CXX_SRC) | sed 's_^\([a-z]\)_objs/\1_g' > depend
 
 -include depend
 
@@ -134,6 +134,19 @@ ispc: print_llvm_src dirs $(OBJS)
 	@echo Creating ispc executable
 	@$(CXX) $(OPT) $(LDFLAGS) -o $@ $(OBJS) $(ISPC_LIBS)
 
+# Use clang as a default compiler, instead of gcc
+clang: ispc
+clang: CXX=clang++
+
+# Build ispc with address sanitizer instrumentation using clang compiler
+# Note that this is not portable build
+asan: clang
+asan: OPT+=-fsanitize=address
+
+# Do debug build, i.e. -O0 -g
+debug: ispc
+debug: OPT=-O0 -g
+
 objs/%.o: %.cpp
 	@echo Compiling $<
 	@$(CXX) $(CXXFLAGS) -o $@ -c $<
diff --git a/doxygen.cfg b/doxygen.cfg
index 6f9c99ef..5601e986 100644
--- a/doxygen.cfg
+++ b/doxygen.cfg
@@ -581,10 +581,12 @@ WARN_LOGFILE           =
 # directories like "/usr/src/myproject". Separate the files or directories
 # with spaces.
 
-INPUT                  = builtins.h \
+INPUT                  = ast.h \
+                         builtins.h \
                          ctx.h \
                          decl.h \
                          expr.h \
+                         func.h \
                          ispc.h \
                          llvmutil.h \
                          module.h \
@@ -593,10 +595,12 @@ INPUT                  = builtins.h \
                          sym.h \
                          type.h \
                          util.h \
+                         ast.cpp \
                          builtins.cpp \
                          ctx.cpp \
                          decl.cpp \
                          expr.cpp \
+                         func.cpp \
                          ispc.cpp \
                          llvmutil.cpp \
                          main.cpp \
@@ -608,7 +612,7 @@ INPUT                  = builtins.h \
                          util.cpp \
                          parse.yy \
                          lex.ll \
-                         builtins-c.c
+                         builtins/builtins.c
 
 # This tag can be used to specify the character encoding of the source files
 # that doxygen parses. Internally doxygen uses the UTF-8 encoding, which is