Move platform-specific flags to a separate file

build/make.config

@@ -5,41 +5,3 @@ objcopy   := llvm-objcopy
 platform  ?= i386_pc
 build     ?= release
 
-ifeq ($(platform),i386_pc)
-clang_res_dir := $(shell $(cc) -print-resource-dir)
-
-kernel_cflags   := --target=i386-none-elf \
-                   -nostdinc \
-                   -nostdlib \
-                   -ffreestanding \
-                   -fno-builtin \
-                   -std=c11 \
-                   -pedantic \
-                   -Wall \
-                   -Wextra
-
-ifeq ($(build),debug)
-kernel_cflags   += -O0 -g
-endif
-
-ifeq ($(build),release)
-kernel_cflags   += -Oz
-endif
-
-kernel_ldflags  := -mcpu=i386 \
-                   --target=i386-none-elf \
-                   -nostdlib \
-                   -ffreestanding \
-                   -fno-builtin \
-                   -fuse-ld=lld \
-                   -flto \
-                   -static \
-                   -Wl,--build-id=none \
-                   $(clang_res_dir)/lib/*/libclang_rt.builtins-i386.a
-
-ifeq ($(build),debug)
-kernel_ldflags  += -g
-endif
-
-endif
-

kernel/Makefile

@@ -2,6 +2,7 @@ include $(srctree)/build/make.config
 
 here := $(srctree)/kernel
 
+include $(here)/make.$(platform).flags
 include $(here)/make.src
 
 all: $(srctree)/out/kernel.elf

kernel/make.i386_pc.flags

@@ -0,0 +1,34 @@
+clang_res_dir := $(shell $(cc) -print-resource-dir)
+
+kernel_cflags   := --target=i386-none-elf \
+                   -nostdinc \
+                   -nostdlib \
+                   -ffreestanding \
+                   -fno-builtin \
+                   -std=c11 \
+                   -pedantic \
+                   -Wall \
+                   -Wextra
+
+ifeq ($(build),debug)
+kernel_cflags   += -O0 -g
+endif
+
+ifeq ($(build),release)
+kernel_cflags   += -Oz
+endif
+
+kernel_ldflags  := -mcpu=i386 \
+                   --target=i386-none-elf \
+                   -nostdlib \
+                   -ffreestanding \
+                   -fno-builtin \
+                   -fuse-ld=lld \
+                   -flto \
+                   -static \
+                   -Wl,--build-id=none \
+                   $(clang_res_dir)/lib/*/libclang_rt.builtins-i386.a
+
+ifeq ($(build),debug)
+kernel_ldflags  += -g
+endif