DF-4807 build.log

$ cc -O -Wall -o ppiwrite_uio ppiwrite_uio.c
(no output -- success)

$ objdump -dr --no-show-raw-insn /root/ppimod/ppi/ppi.ko | awk '/^[0-9a-f]+ <ppiwrite>:/,/^$/' > ppiwrite.dis
(excerpt of ppiwrite.dis — the dropped-check proof)

 58e:	callq  593 <ppiwrite+0xc3>
		58f: R_X86_64_PLT32	uiomove-0x4
 593:	mov    %r15,%rsi          <- setup for next call; %eax (uiomove rc) NEVER tested
 596:	lea    -0x34(%rbp),%rcx
 59a:	mov    %r13d,%edx
 59d:	mov    %rbx,%rdi
 5a0:	callq  5a5 <ppiwrite+0xd5>
		5a1: R_X86_64_PLT32	byte_peripheral_write-0x4
 5a5:	mov    %eax,%r15d
 5a8:	test   %eax,%eax          <- byte_peripheral_write rc IS checked
 5aa:	jne    568 <ppiwrite+0x98>