int i = 1 ;
__asm__ volatile ( "
movl %0, %%eax\n
addl $1, %%eax\n
movl %%eax, %0\n"
: :"g"(i) : "eax"
) ;
gcc -O -S asm1.c.
output asm code:
...
#APP
movl $1, %eax
addl $1, %eax
movl %eax, $1
#NO_APP
...
Neigher the asm1.c or asm1.s can't assembled to a executable file.
But it can compiled by "gcc asm1.c"
How does the gcc optimize programe with "g"(i) ?????
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