inconsistent config.guess output and -mtune for westmere

Vincent Lefevre vincent at vinc17.net
Tue Apr 2 17:06:47 CEST 2024


With GMP 6.3.0:

krakatoa:~/software/gmp-6.3.0> ./config.guess
westmere-pc-linux-gnu
krakatoa:~/software/gmp-6.3.0> ./configure
checking build system type... westmere-pc-linux-gnu
checking host system type... westmere-pc-linux-gnu
checking for a BSD-compatible install... /bin/install -c
checking whether build environment is sane... yes
checking for a thread-safe mkdir -p... /bin/mkdir -p
checking for gawk... gawk
checking whether make sets $(MAKE)... yes
checking whether make supports nested variables... yes
checking whether to enable maintainer-specific portions of Makefiles... no
checking ABI=64
checking compiler gcc -O2 -pedantic -fomit-frame-pointer -m64 ... yes
checking compiler gcc -O2 -pedantic -fomit-frame-pointer -m64  -mtune=nehalem... yes
checking compiler gcc -O2 -pedantic -fomit-frame-pointer -m64 -mtune=nehalem  -march=nehalem... yes
[...]

It uses -mtune=nehalem instead of -mtune=westmere.

According to configure.ac, the choice is apparently based on what
gcc 3.4 knows. But gcc 3.4 is very old...

-- 
Vincent Lefèvre <vincent at vinc17.net> - Web: <https://www.vinc17.net/>
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Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)


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