開始GeekOS之旅的時候,一開始就碰到了小麻煩,在自己64位的Fedora上編譯GeekOS的時候報如下錯誤:
- geekos/lowlevel.o: could not read symbols: File in wrong format
斷定是平台問題.再去官網看了下:
- GeekOS is a tiny operating system kernel for x86 PCs.
看了後就決定換i386系統了,裝上後就發現很多需要配置,太麻煩,稍微思考片刻,記得以前在編譯其它i386代碼時,是可以跨平台的,編譯時搜索lib32庫不就行了嘛.研究了下GeekOS的Makefile.
GeekOS提供的Makefile中是有編譯於X64的配置的.拿 project0的Makefile來說,在第97行(GeekOS-0.3.0) 把TARGECT_CC_PREFIX打開就可以了. 但是你的OS需要安裝Cross-development的開發包.
不過沒關系,還有個方法就是加編譯選項 -m32 和 鏈接選項 -m elf_i386 這樣會在編譯時自動去找lib32.在GeekOS的 Makefile中第100,106,109行改成如下:
- 100 TARGET_CC := $(TARGET_CC_PREFIX)gcc -m32
- 101
- 102 # Host C compiler. This is used to compile programs to execute on
- 103 # the host platform, not the target (x86) platform. On x86/ELF
- 104 # systems, such as Linux and FreeBSD, it can generally be the same
- 105 # as the target C compiler.
- 106 HOST_CC := gcc -m32
- 107
- 108 # Target linker. GNU ld is probably to only one that will work.
- 109 TARGET_LD := $(TARGET_CC_PREFIX)ld -m elf_i386
然後改動後,你可能需要安裝glibc的386版本,fedora安裝如下:
- yum -y install glibc-devel.i686
然後再進行編譯就OK了:
cat geekos/fd_boot.bin geekos/setup.bin geekos/kernel.bin > fd.img
鏡像文件成功生成.
