Hi Sebastian,

FYI, kernel build failed on

tree:   git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb.git merge-result-for-greg
head:   23953bde3e4d6aa8780dc054f6ad9882ac63f4f4
commit: 721e2e91945bc2520d57d795dfe1b502ecec567c [59/99] usb: gadget: libcomposite: move composite.c into libcomposite
config: i386-randconfig-b199 (attached as .config)

All error/warnings:

drivers/built-in.o: In function `uvc_function_set_alt':
webcam.c:(.text+0x14afec): undefined reference to `config_ep_by_speed'
drivers/built-in.o: In function `uvc_function_connect':
(.text+0x14c27f): undefined reference to `usb_function_activate'
drivers/built-in.o: In function `uvc_function_disconnect':
(.text+0x14c328): undefined reference to `usb_function_deactivate'
drivers/built-in.o: In function `webcam_init':
webcam.c:(.init.text+0xc688): undefined reference to `usb_composite_probe'
drivers/built-in.o: In function `webcam_bind':
webcam.c:(.init.text+0xc69d): undefined reference to `usb_string_ids_tab'
webcam.c:(.init.text+0xc6d0): undefined reference to `usb_add_config'
webcam.c:(.init.text+0xc6e0): undefined reference to `usb_composite_overwrite_options'
drivers/built-in.o: In function `uvc_function_bind':
webcam.c:(.init.text+0xca52): undefined reference to `usb_ep_autoconfig'
webcam.c:(.init.text+0xca74): undefined reference to `usb_ep_autoconfig'
webcam.c:(.init.text+0xcaa6): undefined reference to `usb_interface_id'
webcam.c:(.init.text+0xcaca): undefined reference to `usb_interface_id'
webcam.c:(.init.text+0xcc15): undefined reference to `usb_function_deactivate'
drivers/built-in.o: In function `uvc_bind_config':
(.init.text+0xcea4): undefined reference to `usb_string_id'
drivers/built-in.o: In function `uvc_bind_config':
(.init.text+0xcec0): undefined reference to `usb_string_id'
drivers/built-in.o: In function `uvc_bind_config':
(.init.text+0xced8): undefined reference to `usb_string_id'
drivers/built-in.o: In function `uvc_bind_config':
(.init.text+0xcf2f): undefined reference to `usb_add_function'
drivers/built-in.o: In function `webcam_cleanup':
webcam.c:(.exit.text+0x16c0): undefined reference to `usb_composite_unregister'

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0-DAY kernel build testing backend         Open Source Technology Center
Fengguang Wu, Yuanhan Liu                              Intel Corporation