On 2016.10.17 at 19:38 +0100, Will Deacon wrote: > Hi all, > > I'm seeing an arm64 build failure with -rc1 and GCC trunk, although I > believe that the new compiler behaviour at the heart of the problem > has the potential to affect other architectures and other pieces of > kernel code relying on dead-code elimination to remove deliberately > undefined functions. > > The failure looks like: > > | drivers/built-in.o: In function `armada_3700_add_composite_clk': > | > | linux/drivers/clk/mvebu/armada-37xx-periph.c:351: > | undefined reference to `____ilog2_NaN' > | > | linux/drivers/clk/mvebu/armada-37xx-periph.c:351:(.text+0xc72e0): > | relocation truncated to fit: R_AARCH64_CALL26 against undefined symbol > | `____ilog2_NaN' > | > | make: *** [vmlinux] Error 1 >
This is a gcc bug, see: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=72785 -- Markus
