Hello there,
since 3.4.1 the driver scsi/lpfc breaks my build for some unused variables:
drivers/scsi/lpfc/lpfc_scsi.c: In function ‘lpfc_bg_setup_bpl’:
drivers/scsi/lpfc/lpfc_scsi.c:1900:11: error: unused variable ‘rc’ 
[-Werror=unused-variable]
drivers/scsi/lpfc/lpfc_scsi.c: In function ‘lpfc_bg_setup_bpl_prot’:
drivers/scsi/lpfc/lpfc_scsi.c:2037:11: error: unused variable ‘rc’ 
[-Werror=unused-variable]
drivers/scsi/lpfc/lpfc_scsi.c: In function ‘lpfc_bg_setup_sgl’:
drivers/scsi/lpfc/lpfc_scsi.c:2256:11: error: unused variable ‘rc’ 
[-Werror=unused-variable]
drivers/scsi/lpfc/lpfc_scsi.c: In function ‘lpfc_bg_setup_sgl_prot’:
drivers/scsi/lpfc/lpfc_scsi.c:2386:11: error: unused variable ‘rc’ 
[-Werror=unused-variable]
cc1: all warnings being treated as errors

 From the drivers makefile:
ccflags-y += -Werror <- this causes the bad behavior.

=> remove this line or the unused variables
=> decided to remove the unused varaibles for 3.4.x and create a patch 
for it. Maybe you want to queue it up for the 3.4.y stable series!

Greetings
Tobias Klausmann