i386/61306: many binaries crash with "illegal instruction" message (ldexp)

[Alexander Krotov]

>Number:         61306
>Category:       i386
>Synopsis:       many binaries crash with "illegal instruction" message (ldexp)
>Confidential:   no
>Severity:       serious
>Priority:       low
>Responsible:    freebsd-i386
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Tue Jan 13 02:40:13 PST 2004
>Closed-Date:
>Last-Modified:
>Originator:     Alexander Krotov
>Release:        5.2-RELEASE
>Organization:
Solid Information Technology Ltd.
>Environment:
FreeBSD kama 5.2-RELEASE FreeBSD 5.2-RELEASE #0: Mon Jan 12 16:18:06 GMT 2004     root@:/usr/src/sys/i386/compile/KAMA  i386

CPU: AMD Athlon(TM) XP 1700+ (1466.73-MHz 686-class CPU)
          Origin = "AuthenticAMD"  Id = 0x681  Stepping = 1
Features=0x383fbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,P\
GE,MCA,CMOV,PAT,PSE36,MMX,FXSR,SSE>

>Description:
I have installed 5.2 release yesterday and got a lot of problems
with different binaries crashing with "illegal instruction" message.
For example "build world" does not work because awk and troff
crash. fsck_ufs did crash.
>How-To-Repeat:
I have not checked details, this problem might be AMD XP specific.
>Fix:
Quick look into the core files lead me to
/usr/src/lib/libc/i386/gen/ldexp.c
After changing ldexp code like
    double
    ldexp (double value, int exp)
    {
           return value*(1<<exp);
    /*
           double temp, texp, temp2;
           texp = exp;
           ...
    */
    }
the problem has gone. Build world works.

>Release-Note:
>Audit-Trail:
>Unformatted: