Building gnu-nat.c fails with:

../../src/gdb/gnu-nat.c: In function 'inf_set_traced':
../../src/gdb/gnu-nat.c:884: error: suggest parentheses around assignment used 
as truth value
../../src/gdb/gnu-nat.c:884: error: suggest parentheses around assignment used 
as truth value
../../src/gdb/gnu-nat.c: In function 'inf_signal':
(... a few more instances of the same ...)

Turns out that warning comes from the definition of HURD_MSGPORT_RPC,
a 20+ lines system macro...

OK?

-- 
Pedro Alves