Sample Code Compilation Problem

Bolan Meek

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Sep 15, 2013, 1:59:13 PM9/15/13

to apps-...@webmproject.org

After installing the sources, and successfully building, and testing, including using vpxdec to decode a .webm file, and vpxenc to reencode it, I'm hitting a wall trying to compile snippets from http://www.webmproject.org/docs/vp8-sdk/example__simple__encoder.html:

This snippet is just for getting the default configuration:

#include <stdio.h>

#include <vpx/vpx_encoder.h>

#include <vpx/vp8cx.h>

#define interface (vpx_codec_vp8_cx())

int main()

{

vpx_codec_enc_cfg_t cfg;

vpx_codec_err_t errRet;

errRet = vpx_codec_enc_config_default(interface, &cfg, 0);

if (errRet == VPX_CODEC_OK)

puts("got default configuration");

else

puts("failed to get default configuration");

return 0;

}

When I try to compile it, the linker doesn't seem to find certain symbols in libvpx.a:

libvpx $ gcc -lvpx -o experiment/getDefaultConfig experiment/getDefaultConfig.c

/tmp/cckEfNvx.o: In function `vpx_codec_control_VP8_SET_REFERENCE':

getDefaultConfig.c:(.text+0x29): undefined reference to `vpx_codec_control_'

/tmp/cckEfNvx.o: In function `vpx_codec_control_VP8_COPY_REFERENCE':

getDefaultConfig.c:(.text+0x58): undefined reference to `vpx_codec_control_'

/tmp/cckEfNvx.o: In function `vpx_codec_control_VP8_SET_POSTPROC':

getDefaultConfig.c:(.text+0x87): undefined reference to `vpx_codec_control_'

/tmp/cckEfNvx.o: In function `vpx_codec_control_VP8_SET_DBG_COLOR_REF_FRAME':

getDefaultConfig.c:(.text+0xb4): undefined reference to `vpx_codec_control_'

/tmp/cckEfNvx.o: In function `vpx_codec_control_VP8_SET_DBG_COLOR_MB_MODES':

getDefaultConfig.c:(.text+0xe1): undefined reference to `vpx_codec_control_'

/tmp/cckEfNvx.o:getDefaultConfig.c:(.text+0x10e): more undefined references to `vpx_codec_control_' follow

/tmp/cckEfNvx.o: In function `main':

getDefaultConfig.c:(.text+0x4db): undefined reference to `vpx_codec_vp8_cx'

getDefaultConfig.c:(.text+0x4f2): undefined reference to `vpx_codec_enc_config_default'

collect2: error: ld returned 1 exit status

However, vpx_codec_control_ , vpx_codec_vp8_cx and vpx_codec_enc_config_default are all in libvpx.a:

libvpx $ nm /usr/local/lib/libvpx.a | grep -B 2 vpx_codec_control_

vpx_codec.c.o:

0000000000000150 T vpx_codec_control_

libvpx $ nm /usr/local/lib/libvpx.a | grep -B 24 vpx_codec_vp8_cx

vp8_cx_iface.c.o:

U calloc

U free

0000000000000000 r .LC28

U malloc

U vp8_change_config

U vp8_create_compressor

U vp8_get_compressed_data

U vp8_get_preview_raw_frame

U vp8_get_quantizer

U vp8_get_reference

U vp8_receive_raw_frame

U vp8_remove_compressor

U vp8_reverse_trans

U vp8_set_active_map

U vp8_set_internal_size

U vp8_set_reference

U vp8_set_roimap

U vp8_update_entropy

U vp8_update_reference

U vp8_use_as_reference

U vpx_codec_pkt_list_add

U vpx_codec_pkt_list_get

0000000000002cb0 T vpx_codec_vp8_cx

libvpx $ nm /usr/local/lib/libvpx.a | grep -B 3 vpx_codec_enc_config_default

vpx_encoder.c.o:

U memcpy

U vpx_codec_destroy

0000000000000400 T vpx_codec_enc_config_default

If I pass in the object from which vpx_codec_control_ was derived, the linker finds the first of the symbols:

libvpx $ gcc -lvpx -o experiment/getDefaultConfig experiment/getDefaultConfig.c vpx/src/vpx_codec.c.o

/tmp/ccIlU56O.o: In function `main':

getDefaultConfig.c:(.text+0x4db): undefined reference to `vpx_codec_vp8_cx'

getDefaultConfig.c:(.text+0x4f2): undefined reference to `vpx_codec_enc_config_default'

collect2: error: ld returned 1 exit status

If I also pass in the object from which vpx_codec_enc_config_default, that symbol is found:

libvpx $ gcc -lvpx -o experiment/getDefaultConfig experiment/getDefaultConfig.c vpx/src/vpx_encoder.c.o vpx/src/vpx_codec.c.o

/tmp/ccFQgq3T.o: In function `main':

getDefaultConfig.c:(.text+0x4db): undefined reference to `vpx_codec_vp8_cx'

collect2: error: ld returned 1 exit status

If I yet also pass in the object from which vpx_codec_vp8_cx is derived, that symbol is found, but a long list of others are not:

libvpx $ gcc -lvpx -o experiment/getDefaultConfig experiment/getDefaultConfig.c vpx/src/vpx_encoder.c.o vpx/src/vpx_codec.c.o vp8/vp8_cx_iface.c.o

vp8/vp8_cx_iface.c.o: In function `get_param':

vp8_cx_iface.c:(.text+0xa8): undefined reference to `vp8_get_quantizer'

vp8_cx_iface.c:(.text+0xaf): undefined reference to `vp8_reverse_trans'

vp8_cx_iface.c:(.text+0xc8): undefined reference to `vp8_get_quantizer'

vp8/vp8_cx_iface.c.o: In function `vp8e_set_scalemode':

vp8_cx_iface.c:(.text+0x10b): undefined reference to `vp8_set_internal_size'

vp8/vp8_cx_iface.c.o: In function `vp8e_set_activemap':

vp8_cx_iface.c:(.text+0x174): undefined reference to `vp8_set_active_map'

vp8/vp8_cx_iface.c.o: In function `vp8e_set_roi_map':

vp8_cx_iface.c:(.text+0x1e4): undefined reference to `vp8_set_roimap'

vp8/vp8_cx_iface.c.o: In function `vp8e_use_reference':

vp8_cx_iface.c:(.text+0x231): undefined reference to `vp8_use_as_reference'

vp8/vp8_cx_iface.c.o: In function `vp8e_update_reference':

vp8_cx_iface.c:(.text+0x271): undefined reference to `vp8_update_reference'

vp8/vp8_cx_iface.c.o: In function `vp8e_update_entropy':

vp8_cx_iface.c:(.text+0x2b1): undefined reference to `vp8_update_entropy'

vp8/vp8_cx_iface.c.o: In function `vp8e_get_preview':

vp8_cx_iface.c:(.text+0x32e): undefined reference to `vp8_get_preview_raw_frame'

vp8/vp8_cx_iface.c.o: In function `vp8e_destroy':

vp8_cx_iface.c:(.text+0x408): undefined reference to `vp8_remove_compressor'

vp8/vp8_cx_iface.c.o: In function `vp8e_init':

vp8_cx_iface.c:(.text+0x81c): undefined reference to `vp8_rtcd'

vp8_cx_iface.c:(.text+0xfbe): undefined reference to `vp8_create_compressor'

vp8/vp8_cx_iface.c.o: In function `vp8e_get_reference':

vp8_cx_iface.c:(.text+0x1112): undefined reference to `vp8_get_reference'

vp8/vp8_cx_iface.c.o: In function `vp8e_set_reference':

vp8_cx_iface.c:(.text+0x11e2): undefined reference to `vp8_set_reference'

vp8/vp8_cx_iface.c.o: In function `set_param':

vp8_cx_iface.c:(.text+0x1c06): undefined reference to `vp8_change_config'

vp8/vp8_cx_iface.c.o: In function `vp8e_set_config':

vp8_cx_iface.c:(.text+0x237d): undefined reference to `vp8_change_config'

vp8/vp8_cx_iface.c.o: In function `vp8e_encode.part.5':

vp8_cx_iface.c:(.text+0x2507): undefined reference to `vp8_change_config'

vp8_cx_iface.c:(.text+0x25a4): undefined reference to `vp8_use_as_reference'

vp8_cx_iface.c:(.text+0x2709): undefined reference to `vp8_receive_raw_frame'

vp8_cx_iface.c:(.text+0x279d): undefined reference to `vp8_get_compressed_data'

vp8_cx_iface.c:(.text+0x2a8b): undefined reference to `vp8_update_reference'

vp8_cx_iface.c:(.text+0x2ae2): undefined reference to `vp8_update_entropy'

collect2: error: ld returned 1 exit status

From what I interpret from the nm output, these are all from vp8_cx_iface.c.o, so I don't know what further work-around I can attempt. Please, advise.

This is on Linux armalite.bolanm.me 3.2.0-4-amd64 #1 SMP Debian 3.2.41-2 x86_64 GNU/Linux

libvpx $ gcc --version

gcc (Debian 4.7.3-4) 4.7.3

Bolan Meek

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Sep 15, 2013, 2:06:17 PM9/15/13

to apps-...@webmproject.org

Taking a clue from another thread , I tried putting the -lvpx last, saw that it was failing to find math functions, so added -lm, now I'm getting failure to find pthread and semaphore functions:

libvpx $ gcc -o experiment/getDefaultConfig experiment/getDefaultConfig.c -lvpx -lm

/usr/local/lib/libvpx.a(onyx_if.c.o): In function `vp8_change_config':

(.text+0x2100): undefined reference to `sem_wait'

/usr/local/lib/libvpx.a(onyx_if.c.o): In function `vp8_loopfilter_frame':

(.text+0x36cc): undefined reference to `sem_post'

/usr/local/lib/libvpx.a(onyx_if.c.o): In function `vp8_loopfilter_frame':

(.text+0x3e9e): undefined reference to `sem_post'

/usr/local/lib/libvpx.a(onyx_if.c.o): In function `vp8_loopfilter_frame':

(.text+0x4736): undefined reference to `sem_wait'

/usr/local/lib/libvpx.a(onyx_if.c.o): In function `vp8_loopfilter_frame':

(.text+0x592c): undefined reference to `sem_wait'

/usr/local/lib/libvpx.a(onyx_if.c.o): In function `vp8_loopfilter_frame':

(.text+0x5e99): undefined reference to `sem_wait'

/usr/local/lib/libvpx.a(onyx_if.c.o): In function `vp8_get_preview_raw_frame':

(.text+0x7e71): undefined reference to `sem_wait'

/usr/local/lib/libvpx.a(rtcd.c.o): In function `vpx_rtcd':

(.text+0x45b): undefined reference to `pthread_once'

/usr/local/lib/libvpx.a(encodeframe.c.o): In function `vp8_encode_frame':

(.text+0x20b8): undefined reference to `sem_post'

/usr/local/lib/libvpx.a(encodeframe.c.o): In function `vp8_encode_frame':

(.text+0x2216): undefined reference to `sem_post'

/usr/local/lib/libvpx.a(encodeframe.c.o): In function `vp8_encode_frame':

(.text+0x223d): undefined reference to `sem_wait'

/usr/local/lib/libvpx.a(ethreading.c.o):(.text+0x2c): undefined reference to `sem_wait'

/usr/local/lib/libvpx.a(ethreading.c.o):(.text+0x69): undefined reference to `sem_post'

/usr/local/lib/libvpx.a(ethreading.c.o):(.text+0xdf): undefined reference to `sem_wait'

/usr/local/lib/libvpx.a(ethreading.c.o):(.text+0x79d): undefined reference to `sem_post'