From 194dc870a5890e855ecffb30f3b80ba7c88f96d6 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Wed, 27 Jul 2016 20:03:31 -0700 Subject: =?UTF-8?q?Add=20braces=20to=20avoid=20"ambiguous=20=E2=80=98else?= =?UTF-8?q?=E2=80=99"=20compiler=20warnings?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Some of our "for_each_xyz()" macro constructs make gcc unhappy about lack of braces around if-statements inside or outside the loop, because the loop construct itself has a "if-then-else" statement inside of it. The resulting warnings look something like this: drivers/gpu/drm/i915/i915_debugfs.c: In function ‘i915_dump_lrc’: drivers/gpu/drm/i915/i915_debugfs.c:2103:6: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses] if (ctx != dev_priv->kernel_context) ^ even if the code itself is fine. Since the warning is fairly easy to avoid by adding a braces around the if-statement near the for_each_xyz() construct, do so, rather than disabling the otherwise potentially useful warning. (The if-then-else statements used in the "for_each_xyz()" constructs are designed to be inherently safe even with no braces, but in this case it's quite understandable that gcc isn't really able to tell that). This finally leaves the standard "allmodconfig" build with just a handful of remaining warnings, so new and valid warnings hopefully will stand out. Signed-off-by: Linus Torvalds diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c index 1035468..2a6e129 100644 --- a/drivers/gpu/drm/i915/i915_debugfs.c +++ b/drivers/gpu/drm/i915/i915_debugfs.c @@ -2100,9 +2100,10 @@ static int i915_dump_lrc(struct seq_file *m, void *unused) return ret; list_for_each_entry(ctx, &dev_priv->context_list, link) - if (ctx != dev_priv->kernel_context) + if (ctx != dev_priv->kernel_context) { for_each_engine(engine, dev_priv) i915_dump_lrc_obj(m, ctx, engine); + } mutex_unlock(&dev->struct_mutex); diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c index 6a86b5d..7330a66 100644 --- a/drivers/iommu/dmar.c +++ b/drivers/iommu/dmar.c @@ -1871,10 +1871,11 @@ static int dmar_hp_remove_drhd(struct acpi_dmar_header *header, void *arg) /* * All PCI devices managed by this unit should have been destroyed. */ - if (!dmaru->include_all && dmaru->devices && dmaru->devices_cnt) + if (!dmaru->include_all && dmaru->devices && dmaru->devices_cnt) { for_each_active_dev_scope(dmaru->devices, dmaru->devices_cnt, i, dev) return -EBUSY; + } ret = dmar_ir_hotplug(dmaru, false); if (ret == 0) diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 323dac9..4b9040b 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -4272,10 +4272,11 @@ int dmar_check_one_atsr(struct acpi_dmar_header *hdr, void *arg) if (!atsru) return 0; - if (!atsru->include_all && atsru->devices && atsru->devices_cnt) + if (!atsru->include_all && atsru->devices && atsru->devices_cnt) { for_each_active_dev_scope(atsru->devices, atsru->devices_cnt, i, dev) return -EBUSY; + } return 0; } -- cgit v0.10.2