hikaru@n270:/tmp/spectre/spectre-attack-demo-master$ gcc -o spectre spectre.c
In file included from /usr/lib/gcc/i686-linux-gnu/6/include/xmmintrin.h:1249:0,
                 from /usr/lib/gcc/i686-linux-gnu/6/include/x86intrin.h:33,
                 from spectre.c:8:
spectre.c: In function ?readMemoryByte?:
/usr/lib/gcc/i686-linux-gnu/6/include/emmintrin.h:1479:1: error: inlining failed in call to always_inline ?_mm_clflush?: target specific option mismatch
 _mm_clflush (void const *__A)
 ^~~~~~~~~~~
spectre.c:67:7: note: called from here
       _mm_clflush( & array2[i * 512]); /* intrinsic for clflush instruction */
       ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from /usr/lib/gcc/i686-linux-gnu/6/include/xmmintrin.h:1249:0,
                 from /usr/lib/gcc/i686-linux-gnu/6/include/x86intrin.h:33,
                 from spectre.c:8:
/usr/lib/gcc/i686-linux-gnu/6/include/emmintrin.h:1479:1: error: inlining failed in call to always_inline ?_mm_clflush?: target specific option mismatch
 _mm_clflush (void const *__A)
 ^~~~~~~~~~~
spectre.c:72:7: note: called from here
       _mm_clflush( & array1_size);
       ^~~~~~~~~~~~~~~~~~~~~~~~~~~