GCC编译优化设置

检查你的gcc版本：

# gcc --version

* 获取你的cpu的型号：

# cat /proc/cpuinfo

* 在/etc/下建立make.conf文件，并根据cpu的型号写入不同内容(注意你的gcc版本必须在3.0以上)：

i386 (Intel)

CHOST="i386-pc-linux-gnu"
CFLAGS="-march=i386 -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=i386 -O3 -pipe -fomit-frame-pointer"

i486 (Intel)

CHOST="i486-pc-linux-gnu"
CFLAGS="-march=i486 -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=i486 -O3 -pipe -fomit-frame-pointer"

Pentium 1 (Intel)

CHOST="i586-pc-linux-gnu"
CFLAGS="-march=pentium -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=pentium -O3 -pipe -fomit-frame-pointer"

Pentium MMX (Intel)

CHOST="i586-pc-linux-gnu"
CFLAGS="-march=pentium-mmx -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=pentium-mmx -O3 -pipe -fomit-frame-pointer"

Pentium PRO (Intel)

CHOST="i686-pc-linux-gnu"
CFLAGS="-march=pentiumpro -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=pentiumpro -O3 -pipe -fomit-frame-pointer"

Pentium II (Intel)

CHOST="i686-pc-linux-gnu"
CFLAGS="-march=pentium2 -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=pentium2 -O3 -pipe -fomit-frame-pointer"

Celeron (Mendocino), aka Celeron1 (Intel)

CHOST="i686-pc-linux-gnu"
CFLAGS="-march=pentium2 -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=pentium2 -O3 -pipe -fomit-frame-pointer"

Pentium III (Intel)

CHOST="i686-pc-linux-gnu"
CFLAGS="-march=pentium3 -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=pentium3 -O3 -pipe -fomit-frame-pointer"

Celeron (Coppermine) aka Celeron2 (Intel)

CHOST="i686-pc-linux-gnu"
CFLAGS="-march=pentium3 -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=pentium3 -O3 -pipe -fomit-frame-pointer"

Celeron (Willamette) (Intel)

CHOST="i686-pc-linux-gnu"
CFLAGS="-march=pentium4 -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=pentium4 -O3 -pipe -fomit-frame-pointer"

Pentium 4 (Intel)

CHOST="i686-pc-linux-gnu"
CFLAGS="-march=pentium4 -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=pentium4 -O3 -pipe -fomit-frame-pointer"

Eden C3/Ezra (Via)

CHOST="i586-pc-linux-gnu"
CFLAGS="-march=i586 -m3dnow -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=i586 -m3dnow -O3 -pipe -fomit-frame-pointer"

K6 (AMD)

CHOST="i586-pc-linux-gnu"
CFLAGS="-march=k6 -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=k6 -O3 -pipe -fomit-frame-pointer"

K6-2 (AMD)

CHOST="i586-pc-linux-gnu"
CFLAGS="-march=k6-2 -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=k6-2 -O3 -pipe -fomit-frame-pointer"

K6-3 (AMD)

CHOST="i586-pc-linux-gnu"
CFLAGS="-march=k6-3 -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=k6-3 -O3 -pipe -fomit-frame-pointer"

Athlon (AMD)

CHOST="i686-pc-linux-gnu"
CFLAGS="-march=athlon -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=athlon -O3 -pipe -fomit-frame-pointer"

Athlon-tbird, aka K7 (AMD)

CHOST="i686-pc-linux-gnu"
CFLAGS="-march=athlon-tbird -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=athlon-tbird -O3 -pipe -fomit-frame-pointer"

Athlon-tbird XP (AMD)

CHOST="i686-pc-linux-gnu"
CFLAGS="-march=athlon-xp -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=athlon-xp -O3 -pipe -fomit-frame-pointer"

Athlon 4(AMD)

CHOST="i686-pc-linux-gnu"
CFLAGS="-march=athlon-4 -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=athlon-4 -O3 -pipe -fomit-frame-pointer"

Athlon XP (AMD)

CHOST="i686-pc-linux-gnu"
CFLAGS="-march=athlon-xp -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=athlon-xp -O3 -pipe -fomit-frame-pointer"

Athlon MP (AMD)

CHOST="i686-pc-linux-gnu"
CFLAGS="-march=athlon-mp -O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-march=athlon-mp -O3 -pipe -fomit-frame-pointer"

603 (PowerPC)

CHOST="powerpc-unknown-linux-gnu"
CFLAGS="-O3 -pipe -fsigned-char"
CXXFLAGS="-O3 -pipe -fsigned-char"

603e (PowerPC)

CHOST="powerpc-unknown-linux-gnu"
CFLAGS="-O3 -pipe -fsigned-char"
CXXFLAGS="-O3 -pipe -fsigned-char"

604 (PowerPC)

CHOST="powerpc-unknown-linux-gnu"
CFLAGS="-O3 -pipe -fsigned-char"
CXXFLAGS="-O3 -pipe -fsigned-char"

604e (PowerPC)

CHOST="powerpc-unknown-linux-gnu"
CFLAGS="-O3 -pipe -fsigned-char"
CXXFLAGS="-O3 -pipe -fsigned-char"

750 aka as G3 (PowerPC)

CHOST="powerpc-unknown-linux-gnu"
CFLAGS="-mcpu=750 -O3 -pipe -fsigned-char -mpowerpc-gfxopt"
CXXFLAGS="-mcpu=750 -O3 -pipe -fsigned-char -mpowerpc-gfxopt"

7400, aka G4 (PowerPC)

CHOST="powerpc-unknown-linux-gnu"
CFLAGS="-mcpu=7400 -O2 -pipe -fsigned-char -maltivec -mabi=altivec -mpowerpc-gfxopt"
CXXFLAGS="-mcpu=7400 -O2 -pipe -fsigned-char -maltivec -mabi=altivec -mpowerpc-gfxopt"

7450, aka G4 second generation (PowerPC)

CHOST="powerpc-unknown-linux-gnu"
CFLAGS="-mcpu=7450 -O2 -pipe -fsigned-char -maltivec -mabi=altivec -mpowerpc-gfxopt"
CXXFLAGS="-mcpu=7450 -O2 -pipe -fsigned-char -maltivec -mabi=altivec -mpowerpc-gfxopt"

PowerPC (If you don’t know which one)

CHOST="powerpc-unknown-linux-gnu"
CFLAGS="-O3 -pipe -fsigned-char -mpowerpc-gfxopt"
CXXFLAGS="-O3 -pipe -fsigned-char -mpowerpc-gfxopt"

Sparc

CHOST="sparc-unknown-linux-gnu"
CFLAGS="-O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-O3 -pipe -fomit-frame-pointer"

Sparc 64

CHOST="sparc64-unknown-linux-gnu"
CFLAGS="-O3 -pipe -fomit-frame-pointer"
CXXFLAGS="-O3 -pipe -fomit-frame-pointer"

好了，这样做后你编译出的程序运行效率将比以前高很多！只要你有时间，你可以把你的系统如 Red Hat Linux 9 的源代码（后缀.src.rpm）全部重新编译一次，你会发现你的Red Hat Linux系统将比原来快一大截！