From: Jani Nikula <jani.nikula@xxxxxxxxx> commit 410ed5731a6566498a3aa904420aa2e49ba0ba90 upstream. Clang build with UBSAN enabled leads to the following build error: drivers/gpu/drm/i915/intel_engine_cs.o: In function `intel_engine_init_execlist': drivers/gpu/drm/i915/intel_engine_cs.c:411: undefined reference to `__compiletime_assert_411' Again, for this to work the code would first need to be inlined and then constant folded, which doesn't work for Clang because semantic analysis happens before optimization/inlining. Use GEM_BUG_ON() instead of BUILD_BUG_ON(). v2: Use is_power_of_2() from log2.h (Chris) Reported-by: Stephen Boyd <swboyd@xxxxxxxxxxxx> Cc: Stephen Boyd <swboyd@xxxxxxxxxxxx> Cc: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Tested-by: Nathan Chancellor <natechancellor@xxxxxxxxx> Tested-by: Stephen Boyd <swboyd@xxxxxxxxxxxx> Reviewed-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Reviewed-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/20181016122938.18757-2-jani.nikula@xxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/i915/intel_engine_cs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/gpu/drm/i915/intel_engine_cs.c +++ b/drivers/gpu/drm/i915/intel_engine_cs.c @@ -463,7 +463,7 @@ static void intel_engine_init_execlist(s struct intel_engine_execlists * const execlists = &engine->execlists; execlists->port_mask = 1; - BUILD_BUG_ON_NOT_POWER_OF_2(execlists_num_ports(execlists)); + GEM_BUG_ON(!is_power_of_2(execlists_num_ports(execlists))); GEM_BUG_ON(execlists_num_ports(execlists) > EXECLIST_MAX_PORTS); execlists->queue_priority = INT_MIN;
