[Bug target/72736] warning: switch -mcpu=cortex-a53 conflicts with -march=armv8-a switch

[ktkachov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=72736

ktkachov at gcc dot gnu.org changed:

           What    |Removed                     |Added
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                 CC|                            |ktkachov at gcc dot gnu.org

--- Comment #2 from ktkachov at gcc dot gnu.org ---
The crypto instructions use the Advanced SIMD registers and on aarch32 (the arm
gcc port) are therefore enabled by the -mfpu option (unlike on aarch64 where
you can just add +crypto to an -mcpu or -march argument)

To enable them use -mfpu=crypto-neon-fp-armv8.

Note that the -mcpu option is used as a shorthand for an -march + -mtune option
combination.

-mcpu=cortex-a53 is in this case equivalent to -march=armv8-a+crc
-mtune=cortex-a53 which is why you get the complaint about the conflict with
-march=armv8-a