Category: gcc

  • Which architecture should I compile for with GCC?

    Which architecture should I compile for with GCC?

    Last week I wrote about strange assembler messages on new PCs and I mentioned there could be performance issues when you don’t use -march=native. -march=native is very good if you only plan to run your code on a specific computer, or you allow people to compile it themselves from source. So what happens if you…

  • Upgraded to a new computer and getting assembler messages?

    We recently upgraded some of our workstations to the new i7 Haswell series, but when compiling we suddenly got strange messages when compiling the Boost package: Assembler messages: Error: no such instruction: `shlx … Naturally, The error repeated itself with more instructions introduced in the new BMI2 specification BZHI, MULX, PDEP, PEXT, RORX, SARX, SHRX,…