GMP 6.0.0a on AMD A8-6600K

Marc Glisse marc.glisse at
Sun Apr 12 13:46:20 UTC 2015

On Sun, 12 Apr 2015, Marc Glisse wrote:

> What is strange is that the configure test "double -> float" should have 
> generated vcvtsd2ss and caused an error (assuming all AVX instructions are 
> rejected), and that would have caused configure to try adding -mno-avx, but:
> Test compile: double -> float conversion
> configure:7588: gcc -O2 -pedantic -fomit-frame-pointer -m64 -mtune=bdver1 
> -march=bdver1 conftest.c >&5
> configure:7591: $? = 0
> configure:7596: ./a.out || ./b.out || ./a.exe || ./a_out.exe || ./conftest
> configure:7599: $? = 0

Silly me, main never calls the function that has this instruction, so it 
will not fail. Either we need a configure test that actually executes some 
instructions involving float or double (not just compile them), or we 
should be more forceful in adding -mno-avx for *noavx platforms instead of 
waiting for some test to fail.

Marc Glisse

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