title: GCC - toggle each of the instruction set manually without toggling many at once using march?
body: <p>Say I have a code that is planned to run on a computer with SSE2, and I want the compiler to generate code for SSE2. I can take a look at GCC's <a href="https://gcc.gnu.org/onlinedocs/gcc/x86-Options.html" rel="nofollow noreferrer">march list</a> and see that Pentium-m has SSE2 and MMX, so I can do <code>march=pentium-m</code>. How can I toggle each of the instruction set, using something like <code>-march=sse3 -march=mmx</code>?</p>