Re: Software Emulation error

Dear Kyle,

in message [off-list ref] you wrote:

Sorry, I guess more detailed info would be helpful. I'm running a 2.2.13
kernel on a TQM823 board. I have seen this error when using dd to write
to flash. But it's not consistent (sometimes dd works, sometimes it
doesn't). Then I wrote a program using the times() function and it
always fails. I went back and tried this with the original kernel and it
works! I recompiled with and without MATH_EMULATION, but essentially get

Be careful what your running where - if you use  the  old  glibc-1.99
based  tools  which  assume to have a FPU, you MUST run a kernel with
MATH_EMULATION. If you use the CDK to  compile  you  own  stuff  with
glibc-2.x  you  MUST  use  -msoft-float  (in  fact  that's enabled by
default in the CDK).

I have seen similar problem with the old glibc-1.99  tools;  they  go
away when you use a "clean" soft-float-only environment.

the same error. I've tried rebuilding the kernel to what I think are
default settings, but still no luck. What other kernel configs are
relevant?

It's not the kernel, it's the application / library (except that  the
FP emulation code in 2.2.13 had several problems of it's own).

Wolfgang Denk

--
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: wd@denx.de
panic: kernel trap (ignored)

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Wolfgang Denk wrote:

Dear Kyle,

in message [off-list ref] you wrote:

quoted

Sorry, I guess more detailed info would be helpful. I'm running a 2.2.13
kernel on a TQM823 board. I have seen this error when using dd to write
to flash. But it's not consistent (sometimes dd works, sometimes it
doesn't). Then I wrote a program using the times() function and it
always fails. I went back and tried this with the original kernel and it
works! I recompiled with and without MATH_EMULATION, but essentially get

Be careful what your running where - if you use  the  old  glibc-1.99
based  tools  which  assume to have a FPU, you MUST run a kernel with
MATH_EMULATION. If you use the CDK to  compile  you  own  stuff  with
glibc-2.x  you  MUST  use  -msoft-float  (in  fact  that's enabled by
default in the CDK).

This is a little too wierd. I recompiled with -msoft-float and sure
enough the application runs. I then recompiled w/o -msoft-float and
guess what? It still runs. I had also discovered earlier that it would
run under gdb, but not from the shell. I wonder if I might be having a
hardware problem.

Thanks for you help. Kyle.

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