libcurl and __isoc99_sscanf@GLIBC_2.7

libcurl and __isoc99_sscanf@GLIBC_2.7

[Jaya Kumar]

Hi OE friends,

I observed something odd today.

~/oe/setup-scripts$ file
build/tmp-angstrom_2010_x-eglibc/work/armv7a-angstrom-linux-gnueabi/curl-7.24.0-r0/package/usr/lib/libcurl.so.5.2.0
build/tmp-angstrom_2010_x-eglibc/work/armv7a-angstrom-linux-gnueabi/curl-7.24.0-r0/package/usr/lib/libcurl.so.5.2.0:
ELF 32-bit LSB shared object, ARM, version 1 (SYSV), dynamically
linked, stripped

~/oe/setup-scripts$ readelf -a
build/tmp-angstrom_2010_x-eglibc/work/armv7a-angstrom-linux-gnueabi/curl-7.24.0-r0/package/usr/lib/libcurl.so.5.2.0
| egrep GLIBC_2.7
    30: 00000000     0 FUNC    GLOBAL DEFAULT  UND __isoc99_sscanf@GLIBC_2.7 (7)
  01c:   2 (GNUTLS_1_4)    6 (GCRYPT_1.2)    7 (GLIBC_2.7)     2 (GNUTLS_1_4)
  0x0070:   Name: GLIBC_2.7  Flags: none  Version: 7

I was wondering if that is correct behavior? I don't have an
understanding of why sscanf seems to have a dependency on glibc 2.7. I
encountered this issue because I took the curl libs, unpacked them in
my metatoolchain libs, and then tried to link my app against it and
got:

arm-angstrom-linux-gnueabi-gcc -o curltest curltest.c
-I/home/test/oemetatoolchain/usr/include
-Wl,-rpath=/home/test/oemetatoolchain/usr/lib/:/home/test/oemetatoolchain/lib/
-lcurl
../../usr/lib//libcurl.so: undefined reference to `__isoc99_sscanf@GLIBC_2.7'
collect2: ld returned 1 exit status

So the only fault seems to be with sscanf. Other functions seem to be
fine, eg: sprintf:
   164: 00000000     0 FUNC    GLOBAL DEFAULT  UND sprintf@GLIBC_2.4 (3)

Suggestions or advice would be greatly appreciated.

Thanks,
jayakumar

Re: libcurl and __isoc99_sscanf@GLIBC_2.7

[Khem Raj]

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On 6/7/2012 4:20 AM, Jaya Kumar wrote:
> I was wondering if that is correct behavior? I don't have an 
> understanding of why sscanf seems to have a dependency on glibc
> 2.7. I encountered this issue because I took the curl libs,
> unpacked them in my metatoolchain libs, and then tried to link my
> app against it and got:

how did you build those curl libs ?
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Re: libcurl and __isoc99_sscanf@GLIBC_2.7

[Jaya Kumar]

On Sun, Jun 10, 2012 at 7:28 AM, Khem Raj <raj.khem@gmail.com> wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> On 6/7/2012 4:20 AM, Jaya Kumar wrote:
>> I was wondering if that is correct behavior? I don't have an
>> understanding of why sscanf seems to have a dependency on glibc
>> 2.7. I encountered this issue because I took the curl libs,
>> unpacked them in my metatoolchain libs, and then tried to link my
>> app against it and got:
>
> how did you build those curl libs ?

Hi Khem,

Thanks for your reply. I had built curl using OE, ie:
MACHINE=beagleboard bitbake curl. I figured out the source of my
problem. The meta-toolchain I had been using was using an older libc,
whereas my OE build (since I had used oebb.sh update) had switched to
using eglibc where the c99 extensions were present. So I switched to
using the prebuilt toolchain and everything works fine now.

Thanks,
jayakumar