How do I find out whether a particular gcc supports a
particular subarchitecture, e.g. MMX instructions, by default?
If the gcc has been configured --with-arch=XXXX,
I can get that value using:
gcc -v --help 2>&1 | grep 'Configured with'
but if the arch has defaulted based on the target triplet,
it is less obvious. Is it documented that
configure i486-xxxxxx
is equivalent to
configure .... --with-arch=i486
?
Even better, it would be nice if gcc -v --help
said something like:
mmx support is enabled (use -mno-mmx to disable it)
sse support is disabled (use -msse to enable it)
I would have guessed gcc -dumpspecs would give me
this kind of information, but it appears not to.
--
Summary: gcc help should provide subarchitecture details
Product: gcc
Version: 4.2.3
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: driver
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: martinrb at google dot com
GCC host triplet: x86_64-linux-gnu
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37551
