Hi there, I have a Sun / Cobalt Qube 3 with an AMD K6-2+ CPU, and gcc seems to be misdetecting it as an Athlon when using -march=native
# gcc -v -Q --help=target -march=native 2>&1 | grep march /usr/libexec/gcc/i586-pc-linux-gnu/4.5.2/cc1 -v help-dummy -D_FORTIFY_SOURCE=2 -march=athlon --param l1-cache-size=32 --param l1-cache-line-size=32 --param l2-cache-size=128 -mtune=athlon -dumpbase help-dummy -auxbase help-dummy -version -fhelp=target -o /tmp/ccQrke9q.s -march= athlon # I've tried a couple of different versions of gcc - 4.4.4 and 4.5.2 - but they both show the same. Someone on the linux-cobalt mailing list can also reproduce. When I compile nano using `-march=i586`, `-march=k6-2` or `-march=k6-3` it works fine. If I compile it with `-march=native` then nano crashes on startup saying "illegal instruction". /proc/cpuinfo seems to show the CPU correctly: # cat /proc/cpuinfo processor : 0 vendor_id : AuthenticAMD cpu family : 5 model : 13 model name : AMD-K6(tm)-III Processor stepping : 4 cpu MHz : 448.140 cache size : 128 KB fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 1 wp : yes flags : fpu vme de pse tsc msr cx8 pge mmx syscall 3dnowext 3dnow k6_mtrr bogomips : 896.28 clflush size : 32 cache_alignment : 32 address sizes : 32 bits physical, 32 bits virtual power management: ts fid vid # AIUI the K6-2+ is architecturally the same as a K6-3, so I assume this is fine. The family & model above match what wikipedia says it should be for a K6-2+ (although they're also the same for a K6-3+). The Cobalt Qube 3 is slightly unusual in that it doesn't have a regular BIOS, but OTOH it doesn't seem much different from a regular PC - it uses standard EIDE hard-drives (SCSI optional) and has a PCI slot. A patch [1] is applied to the 2.6.36.2 vanilla kernel but I think this is just to support ACPI, the LCD panel, the front LED and measuring the fan speed. I don't think these things should affect gcc's detection of the CPU, but I thought I should mention it to be on the safe side. I'm a complete n00b here, and don't really know how to debug further. My C isn't really up to digging around in gcc's source - not blindly, at least - and seeing if this is the Qube's fault or what. If anyone could give me *any* pointers at all, I'd be grateful. I don't know whether I should be simply reporting this as a bug, or asking for an explanation of how gcc determines CPU type so I can compare with what I'm seeing. Thanks in advance for any suggestions, Stroller. [1] http://downloads.raqcop.com/cobalt_ipcop/extras/cobalt-kernel-patches/2.6-kernel/linux-cobalt-2.6.36.patch http://downloads.raqcop.com/cobalt_ipcop/extras/Cobalt-Server-Kernels/configs/2.6.36.2-3-cobalt.config.txt
