Re: Segmentation fault at dbConvert.c in Ubuntu 32/64 bit

[Ralph Lange <ralph.lange@gmx.de>]

Hi Carsten,

The default value for precision used when you comment out the lines you mention is 6.

Can you achieve the same (i.e. avoid segfaults) by setting PREC to 6 in your database?

If yes: which PREC values cause segfaults?

Cheers,
~Ralph

On Tue, Feb 21, 2017 at 9:15 AM, Carsten Winkler <carsten.winkler@helmholtz-berlin.de> wrote:

I forgot to give you the used db entry. Here it is:

record(waveform, "caLab:waveString")
{
    field(DESC, "String waveform record")
    field(NELM, 48)
    field(FTVL, "STRING")
    field (PINI, "YES")
    field (PREC, 3)

}


Am 20.02.2017 um 15:40 schrieb Carsten Winkler:
> Hi there,
>
> I always run into a  "Segmentation fault" in function "putFloatString" |
> "putDoubleString" of BASE/src/db/dbConvert.c
>
> When I comment out following lines (call of get_precision) everything is
> working again:
> 3947
> 3948
> 4157
> 4158
>
> Test system
> =================================================
> Ubunu 16.04 (64 bit)
> EPICS BASE 3.14.12.6 (64 bit)
>
>
> To check the error, I used this code:
> test.cpp
> =================================================
>
> #include <malloc.h>
> #include <cadef.h>
> //#define DOUBLE
>
> using namespace std;
>
> int main() {
>     chid chanID;
>     int iNumber = 1;
>     int timeout = 0;
>     void *pValue = 0x0;
>
>     ca_context_create(ca_enable_preemptive_callback);
> #if defined DOUBLE
>     pValue = (double*)malloc(iNumber*sizeof(double));
>     for(int i=0; i<iNumber; i++) {
>         ((double*)pValue)[i] = (double)((1+i)*3.1415926535897);
>     }
> #else
>     pValue = (float*)malloc(iNumber*sizeof(float));
>     for(int i=0; i<iNumber; i++) {
>         ((float*)pValue)[i] = (float)((1+i)*3.1415926535897);
>     }
> #endif
>     ca_create_channel("caLab:waveString", 0, 0, 50, &chanID);
>     timeout = 3000;
>     while(ca_state(chanID) != cs_conn && timeout--) {
>         epicsThreadSleep(.001);
>     }
> #if defined DOUBLE
>     ca_array_put(DBR_DOUBLE, 1, chanID, pValue);
> #else
>     ca_array_put(DBR_FLOAT, 1, chanID, pValue);
> #endif
>     ca_context_destroy();
>     free(pValue);
>     return 0;
> }
>
> g++ -I/usr/local/epics/base-3.14.12.6/include/os/Linux
> -I/usr/local/epics/base-3.14.12.6/include -O0 -g3 -Wall -c
> -fmessage-length=0 -MMD -MP -MF"test.d" -MT"test.d" -o "test.o" "test.cpp"
> g++ -L/usr/local/epics/base-3.14.12.6/lib/linux-x86_64 -o "test"
> test.o   -lCom -lca
>
> Any advice to solve this issue?
>
> Best regards
> Carsten Winkler
>
> PS Same problem in 32 bit systems
>
>
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>
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>
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>
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>
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________________________________

Helmholtz-Zentrum Berlin für Materialien und Energie GmbH

Mitglied der Hermann von Helmholtz-Gemeinschaft Deutscher Forschungszentren e.V.

Aufsichtsrat: Vorsitzender Dr. Karl Eugen Huthmacher, stv. Vorsitzende Dr. Jutta Koch-Unterseher
Geschäftsführung: Prof. Dr. Anke Rita Kaysser-Pyzalla, Thomas Frederking

Sitz Berlin, AG Charlottenburg, 89 HRB 5583

Postadresse:
Hahn-Meitner-Platz 1
D-14109 Berlin

http://www.helmholtz-berlin.de