| View previous topic :: View next topic |
| Author |
Message |
shim747
n00b
Joined: 09 Apr 2021
Posts: 1
|
 Posted: Fri Apr 09, 2021 3:26 pm Post subject: Can't find flags for my old pc's cpu - intel pentium merom |
 |
|
Hello, i wanted to install gentoo on my old computer and followed the instructions in the handbook but then there was a part with flags and there were "safe flags" recommended for many intel and amd cpus but mine didn't appear there. I saw ones for older and newer pentium processors, but there weren't ones for pentium merom generation.
Can anyone help me with setting them up for this processor? |
|
| Back to top |
|
 |
abdus
Apprentice
Joined: 10 Feb 2021
Posts: 189
Location: bandung
|
|
| Back to top |
|
|
mike155
Advocate
Joined: 17 Sep 2010
Posts: 4438
Location: Frankfurt, Germany
|
| Posted: Fri Apr 09, 2021 3:39 pm Post subject: |
|
|
Look at Safe CFLAGS and choose the settings for "Automatic CPU detection by the compiler":
| Code: | COMMON_FLAGS="-O2 -pipe -march=native"
CFLAGS="${COMMON_FLAGS}"
CXXFLAGS="${COMMON_FLAGS}" |
Use the program 'cpuid2cpuflags' to get the CPU flags:
EDIT: abdus was faster  |
|
| Back to top |
|
|
NeddySeagoon
Administrator
Joined: 05 Jul 2003
Posts: 54300
Location: 56N 3W
|
| Posted: Fri Apr 09, 2021 3:52 pm Post subject: |
|
|
shim747,
Welcome to gentoo.
The Intel pentium merom is a whole range of low power CPUs.
| Code: | | CFLAGS="-march=native -O2 -pipe" |
and the same for CXXFLAGS is a good place to start.
gcc will work out what in correct for the CPU its running on.
To see what gcc will do, run | Code: | | gcc -### -E - -march=native 2>&1 | sed -r '/cc1/!d;s/(")|(^.* - )|( -mno-[^\ ]+)//g' |
I get | Code: | | -march=amdfam10 -mmmx -m3dnow -msse -msse2 -msse3 -msse4a -mcx16 -msahf -mpopcnt -mabm -mlzcnt -mprfchw -mfxsr --param l1-cache |
Something to be aware of is that should you want to build code on another system to run on your merom you must not use -march=native, as gcc will build for the system its actually running on.
Its safe to use the output of that gcc command in place of -march=native if you wish.
Do leave a comment in make.conf to remind yourself where it came from though.
_________________
Regards,
NeddySeagoon
Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail. |
|
| Back to top |
|
|
|
Installing Gentoo
