From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tom Rini Date: Wed, 5 Aug 2020 14:37:44 -0400 Subject: [PATCH] log: Allow LOG_DEBUG to always enable log output In-Reply-To: References: <20200727022735.1435481-1-sjg@chromium.org> <20200805121819.GA24776@bill-the-cat> <8708d832-cdc2-9875-2ce1-848c0a8869be@gmx.de> <20200805125609.GL6965@bill-the-cat> Message-ID: <20200805183744.GP6965@bill-the-cat> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On Wed, Aug 05, 2020 at 08:31:55PM +0200, Heinrich Schuchardt wrote: > On 05.08.20 14:56, Tom Rini wrote: > > On Wed, Aug 05, 2020 at 02:54:05PM +0200, Heinrich Schuchardt wrote: > >> On 05.08.20 14:18, Tom Rini wrote: > >>> On Sun, Jul 26, 2020 at 08:27:35PM -0600, Simon Glass wrote: > >>> > >>>> At present if CONFIG_LOG enabled, putting LOG_DEBUG at the top of a file > >>>> (before log.h inclusion) causes _log() to be executed for every log() > >>>> call, regardless of the build- or run-time logging level. > >>>> > >>>> However there is no guarantee that the log record will actually be > >>>> displayed. If the current log level is lower than LOGL_DEBUG then it will > >>>> not be. > >>>> > >>>> Add a way to signal that the log record should always be displayed and > >>>> update log_passes_filters() to handle this. > >>>> > >>>> Signed-off-by: Simon Glass > >>> > >>> This exposes an underlying problem with LOG and clang I believe: > >>> https://gitlab.denx.de/u-boot/u-boot/-/jobs/135789 > >>> > >> > >> include/log.h:147:44: note: expanded from macro 'log' > >> if (CONFIG_IS_ENABLED(LOG) && (_LOG_DEBUG || _l <= > >> _LOG_MAX_LEVEL)) \ > >> ^ > >> drivers/misc/p2sb_emul.c:197:10: error: converting the enum constant to > >> a boolean [-Werror,-Wint-in-bool-context] > >> > >> This seems to be a Clang bug. _LOG_DEBUG is not an enum: > >> > >> #if CONFIG_IS_ENABLED(LOG) > >> #ifdef LOG_DEBUG > >> #define _LOG_DEBUG??????1 > >> #else > >> #define _LOG_DEBUG??????0 > >> #endif > >> > >> So there seems to be a bug in the Clang you used. > >> > >> Compiling with clang on Debian Bullseye does not show the problem: > >> > >> make HOSTCC=clang sandbox_defconfig > >> make HOSTCC=clang CC=clang -j8 > >> > >> clang version 9.0.1-13 > >> LLVM version 9.0.1 > >> > >> Which Clang version did you use? > >> > >> This is the change that added the test: > >> https://reviews.llvm.org/D63082 > >> > >> -Wint-in-bool-context seems to be new in Clang 10. > >> > >> All over the U-Boot code we assume that a non-zero integer is true. Do > >> we really want to enable -Wint-in-bool-context? > > > > I'm using the official Clang 10 stable builds. > > > > Do you really want to forbid using integers as booleans > (-Wint-in-bool-context)? So, interesting. The Linux kernel isn't disabling this warning. It's mentioned in two commits, one of which is "clang found a bug here", of which this is not the case. The other is more like ours: commit 968e5170939662341242812b9c82ef51cf140a33 Author: Nathan Chancellor Date: Thu Sep 26 09:22:59 2019 -0700 tracing: Fix clang -Wint-in-bool-context warnings in IF_ASSIGN macro After r372664 in clang, the IF_ASSIGN macro causes a couple hundred warnings along the lines of: kernel/trace/trace_output.c:1331:2: warning: converting the enum constant to a boolean [-Wint-in-bool-context] kernel/trace/trace.h:409:3: note: expanded from macro 'trace_assign_type' IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, ^ kernel/trace/trace.h:371:14: note: expanded from macro 'IF_ASSIGN' WARN_ON(id && (entry)->type != id); \ ^ 264 warnings generated. This warning can catch issues with constructs like: if (state == A || B) where the developer really meant: if (state == A || state == B) This is currently the only occurrence of the warning in the kernel tree across defconfig, allyesconfig, allmodconfig for arm32, arm64, and x86_64. Add the implicit '!= 0' to the WARN_ON statement to fix the warnings and find potential issues in the future. Link: https://github.com/llvm/llvm-project/commit/28b38c277a2941e9e891b2db30652cfd962f070b Link: https://github.com/ClangBuiltLinux/linux/issues/686 Link: http://lkml.kernel.org/r/20190926162258.466321-1-natechancellor at gmail.com Reviewed-by: Nick Desaulniers Signed-off-by: Nathan Chancellor Signed-off-by: Steven Rostedt (VMware) Which is like our case, and reworking the test to be explicit. I lean towards that. -- Tom -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 659 bytes Desc: not available URL: