checkpatch.pl

				my $ctx = $s;
				substr($ctx, 0, $name_len + 1, '');
				$ctx =~ s/\)[^\)]*$//;

				for my $arg (split(/\s*,\s*/, $ctx)) {
					if ($arg =~ /^(?:const\s+)?($Ident)(?:\s+$Sparse)*\s*\**\s*(:?\b$Ident)?$/s || $arg =~ /^($Ident)$/s) {

						possible($1, "D:" . $s);
					}
				}
			}

		}

#
# Checks which may be anchored in the context.
#

# Check for switch () and associated case and default
# statements should be at the same indent.
		if ($line=~/\bswitch\s*\(.*\)/) {
			my $err = '';
			my $sep = '';
			my @ctx = ctx_block_outer($linenr, $realcnt);
			shift(@ctx);
			for my $ctx (@ctx) {
				my ($clen, $cindent) = line_stats($ctx);
				if ($ctx =~ /^\+\s*(case\s+|default:)/ &&
							$indent != $cindent) {
					$err .= "$sep$ctx\n";
					$sep = '';
				} else {
					$sep = "[...]\n";
				}
			}
			if ($err ne '') {
				ERROR("SWITCH_CASE_INDENT_LEVEL",
				      "switch and case should be at the same indent\n$hereline$err");
			}
		}

# if/while/etc brace do not go on next line, unless defining a do while loop,
# or if that brace on the next line is for something else
		if ($line =~ /(.*)\b((?:if|while|for|switch)\s*\(|do\b|else\b)/ && $line !~ /^.\s*\#/) {
			my $pre_ctx = "$1$2";

			my ($level, @ctx) = ctx_statement_level($linenr, $realcnt, 0);

			if ($line =~ /^\+\t{6,}/) {
				WARN("DEEP_INDENTATION",
				     "Too many leading tabs - consider code refactoring\n" . $herecurr);
			}

			my $ctx_cnt = $realcnt - $#ctx - 1;
			my $ctx = join("\n", @ctx);

			my $ctx_ln = $linenr;
			my $ctx_skip = $realcnt;

			while ($ctx_skip > $ctx_cnt || ($ctx_skip == $ctx_cnt &&
					defined $lines[$ctx_ln - 1] &&
					$lines[$ctx_ln - 1] =~ /^-/)) {
				##print "SKIP<$ctx_skip> CNT<$ctx_cnt>\n";
				$ctx_skip-- if (!defined $lines[$ctx_ln - 1] || $lines[$ctx_ln - 1] !~ /^-/);
				$ctx_ln++;
			}

			#print "realcnt<$realcnt> ctx_cnt<$ctx_cnt>\n";
			#print "pre<$pre_ctx>\nline<$line>\nctx<$ctx>\nnext<$lines[$ctx_ln - 1]>\n";

			if ($ctx !~ /{\s*/ && defined($lines[$ctx_ln -1]) && $lines[$ctx_ln - 1] =~ /^\+\s*{/) {
				ERROR("OPEN_BRACE",
				      "that open brace { should be on the previous line\n" .
					"$here\n$ctx\n$rawlines[$ctx_ln - 1]\n");
			}
			if ($level == 0 && $pre_ctx !~ /}\s*while\s*\($/ &&
			    $ctx =~ /\)\s*\;\s*$/ &&
			    defined $lines[$ctx_ln - 1])
			{
				my ($nlength, $nindent) = line_stats($lines[$ctx_ln - 1]);
				if ($nindent > $indent) {
					WARN("TRAILING_SEMICOLON",
					     "trailing semicolon indicates no statements, indent implies otherwise\n" .
						"$here\n$ctx\n$rawlines[$ctx_ln - 1]\n");
				}
			}
		}

# Check relative indent for conditionals and blocks.
		if ($line =~ /\b(?:(?:if|while|for)\s*\(|do\b)/ && $line !~ /^.\s*#/ && $line !~ /\}\s*while\s*/) {
			($stat, $cond, $line_nr_next, $remain_next, $off_next) =
				ctx_statement_block($linenr, $realcnt, 0)
					if (!defined $stat);
			my ($s, $c) = ($stat, $cond);

			substr($s, 0, length($c), '');

			# Make sure we remove the line prefixes as we have
			# none on the first line, and are going to readd them
			# where necessary.
			$s =~ s/\n./\n/gs;

			# Find out how long the conditional actually is.
			my @newlines = ($c =~ /\n/gs);
			my $cond_lines = 1 + $#newlines;

			# We want to check the first line inside the block
			# starting at the end of the conditional, so remove:
			#  1) any blank line termination
			#  2) any opening brace { on end of the line
			#  3) any do (...) {
			my $continuation = 0;
			my $check = 0;
			$s =~ s/^.*\bdo\b//;
			$s =~ s/^\s*{//;
			if ($s =~ s/^\s*\\//) {
				$continuation = 1;
			}
			if ($s =~ s/^\s*?\n//) {
				$check = 1;
				$cond_lines++;
			}

			# Also ignore a loop construct at the end of a
			# preprocessor statement.
			if (($prevline =~ /^.\s*#\s*define\s/ ||
			    $prevline =~ /\\\s*$/) && $continuation == 0) {
				$check = 0;
			}

			my $cond_ptr = -1;
			$continuation = 0;
			while ($cond_ptr != $cond_lines) {
				$cond_ptr = $cond_lines;

				# If we see an #else/#elif then the code
				# is not linear.
				if ($s =~ /^\s*\#\s*(?:else|elif)/) {
					$check = 0;
				}

				# Ignore:
				#  1) blank lines, they should be at 0,
				#  2) preprocessor lines, and
				#  3) labels.
				if ($continuation ||
				    $s =~ /^\s*?\n/ ||
				    $s =~ /^\s*#\s*?/ ||
				    $s =~ /^\s*$Ident\s*:/) {
					$continuation = ($s =~ /^.*?\\\n/) ? 1 : 0;
					if ($s =~ s/^.*?\n//) {
						$cond_lines++;
					}
				}
			}

			my (undef, $sindent) = line_stats("+" . $s);
			my $stat_real = raw_line($linenr, $cond_lines);

			# Check if either of these lines are modified, else
			# this is not this patch's fault.
			if (!defined($stat_real) ||
			    $stat !~ /^\+/ && $stat_real !~ /^\+/) {
				$check = 0;
			}
			if (defined($stat_real) && $cond_lines > 1) {
				$stat_real = "[...]\n$stat_real";
			}

			#print "line<$line> prevline<$prevline> indent<$indent> sindent<$sindent> check<$check> continuation<$continuation> s<$s> cond_lines<$cond_lines> stat_real<$stat_real> stat<$stat>\n";

			if ($check && (($sindent % 8) != 0 ||
			    ($sindent <= $indent && $s ne ''))) {
				WARN("SUSPECT_CODE_INDENT",
				     "suspect code indent for conditional statements ($indent, $sindent)\n" . $herecurr . "$stat_real\n");
			}
		}

		# Track the 'values' across context and added lines.
		my $opline = $line; $opline =~ s/^./ /;
		my ($curr_values, $curr_vars) =
				annotate_values($opline . "\n", $prev_values);
		$curr_values = $prev_values . $curr_values;
		if ($dbg_values) {
			my $outline = $opline; $outline =~ s/\t/ /g;
			print "$linenr > .$outline\n";
			print "$linenr > $curr_values\n";
			print "$linenr >  $curr_vars\n";
		}
		$prev_values = substr($curr_values, -1);

#ignore lines not being added
		if ($line=~/^[^\+]/) {next;}

# TEST: allow direct testing of the type matcher.
		if ($dbg_type) {
			if ($line =~ /^.\s*$Declare\s*$/) {
				ERROR("TEST_TYPE",
				      "TEST: is type\n" . $herecurr);
			} elsif ($dbg_type > 1 && $line =~ /^.+($Declare)/) {
				ERROR("TEST_NOT_TYPE",
				      "TEST: is not type ($1 is)\n". $herecurr);
			}
			next;
		}
# TEST: allow direct testing of the attribute matcher.
		if ($dbg_attr) {
			if ($line =~ /^.\s*$Modifier\s*$/) {
				ERROR("TEST_ATTR",
				      "TEST: is attr\n" . $herecurr);
			} elsif ($dbg_attr > 1 && $line =~ /^.+($Modifier)/) {
				ERROR("TEST_NOT_ATTR",
				      "TEST: is not attr ($1 is)\n". $herecurr);
			}
			next;
		}

# check for initialisation to aggregates open brace on the next line
		if ($line =~ /^.\s*{/ &&
		    $prevline =~ /(?:^|[^=])=\s*$/) {
			ERROR("OPEN_BRACE",
			      "that open brace { should be on the previous line\n" . $hereprev);
		}

#
# Checks which are anchored on the added line.
#

# check for malformed paths in #include statements (uses RAW line)
		if ($rawline =~ m{^.\s*\#\s*include\s+[<"](.*)[">]}) {
			my $path = $1;
			if ($path =~ m{//}) {
				ERROR("MALFORMED_INCLUDE",
				      "malformed #include filename\n" . $herecurr);
			}
			if ($path =~ "^uapi/" && $realfile =~ m@\binclude/uapi/@) {
				ERROR("UAPI_INCLUDE",
				      "No #include in ...include/uapi/... should use a uapi/ path prefix\n" . $herecurr);
			}
		}

# no C99 // comments
		if ($line =~ m{//}) {
			ERROR("C99_COMMENTS",
			      "do not use C99 // comments\n" . $herecurr);
		}
		# Remove C99 comments.
		$line =~ s@//.*@@;
		$opline =~ s@//.*@@;

# EXPORT_SYMBOL should immediately follow the thing it is exporting, consider
# the whole statement.
#print "APW <$lines[$realline_next - 1]>\n";
		if (defined $realline_next &&
		    exists $lines[$realline_next - 1] &&
		    !defined $suppress_export{$realline_next} &&
		    ($lines[$realline_next - 1] =~ /EXPORT_SYMBOL.*\((.*)\)/ ||
		     $lines[$realline_next - 1] =~ /EXPORT_UNUSED_SYMBOL.*\((.*)\)/)) {
			# Handle definitions which produce identifiers with
			# a prefix:
			#   XXX(foo);
			#   EXPORT_SYMBOL(something_foo);
			my $name = $1;
			if ($stat =~ /^(?:.\s*}\s*\n)?.([A-Z_]+)\s*\(\s*($Ident)/ &&
			    $name =~ /^${Ident}_$2/) {
#print "FOO C name<$name>\n";
				$suppress_export{$realline_next} = 1;

			} elsif ($stat !~ /(?:
				\n.}\s*$|
				^.DEFINE_$Ident\(\Q$name\E\)|
				^.DECLARE_$Ident\(\Q$name\E\)|
				^.LIST_HEAD\(\Q$name\E\)|
				^.(?:$Storage\s+)?$Type\s*\(\s*\*\s*\Q$name\E\s*\)\s*\(|
				\b\Q$name\E(?:\s+$Attribute)*\s*(?:;|=|\[|\()
			    )/x) {
#print "FOO A<$lines[$realline_next - 1]> stat<$stat> name<$name>\n";
				$suppress_export{$realline_next} = 2;
			} else {
				$suppress_export{$realline_next} = 1;
			}
		}
		if (!defined $suppress_export{$linenr} &&
		    $prevline =~ /^.\s*$/ &&
		    ($line =~ /EXPORT_SYMBOL.*\((.*)\)/ ||
		     $line =~ /EXPORT_UNUSED_SYMBOL.*\((.*)\)/)) {
#print "FOO B <$lines[$linenr - 1]>\n";
			$suppress_export{$linenr} = 2;
		}
		if (defined $suppress_export{$linenr} &&
		    $suppress_export{$linenr} == 2) {
			WARN("EXPORT_SYMBOL",
			     "EXPORT_SYMBOL(foo); should immediately follow its function/variable\n" . $herecurr);
		}

# check for global initialisers.
		if ($line =~ /^.$Type\s*$Ident\s*(?:\s+$Modifier)*\s*=\s*(0|NULL|false)\s*;/) {
			ERROR("GLOBAL_INITIALISERS",
			      "do not initialise globals to 0 or NULL\n" .
				$herecurr);
		}
# check for static initialisers.
		if ($line =~ /\bstatic\s.*=\s*(0|NULL|false)\s*;/) {
			ERROR("INITIALISED_STATIC",
			      "do not initialise statics to 0 or NULL\n" .
				$herecurr);
		}

# check for static const char * arrays.
		if ($line =~ /\bstatic\s+const\s+char\s*\*\s*(\w+)\s*\[\s*\]\s*=\s*/) {
			WARN("STATIC_CONST_CHAR_ARRAY",
			     "static const char * array should probably be static const char * const\n" .
				$herecurr);
               }

# check for static char foo[] = "bar" declarations.
		if ($line =~ /\bstatic\s+char\s+(\w+)\s*\[\s*\]\s*=\s*"/) {
			WARN("STATIC_CONST_CHAR_ARRAY",
			     "static char array declaration should probably be static const char\n" .
				$herecurr);
               }

# check for declarations of struct pci_device_id
		if ($line =~ /\bstruct\s+pci_device_id\s+\w+\s*\[\s*\]\s*\=\s*\{/) {
			WARN("DEFINE_PCI_DEVICE_TABLE",
			     "Use DEFINE_PCI_DEVICE_TABLE for struct pci_device_id\n" . $herecurr);
		}

# check for new typedefs, only function parameters and sparse annotations
# make sense.
		if ($line =~ /\btypedef\s/ &&
		    $line !~ /\btypedef\s+$Type\s*\(\s*\*?$Ident\s*\)\s*\(/ &&
		    $line !~ /\btypedef\s+$Type\s+$Ident\s*\(/ &&
		    $line !~ /\b$typeTypedefs\b/ &&
		    $line !~ /\b__bitwise(?:__|)\b/) {
			WARN("NEW_TYPEDEFS",
			     "do not add new typedefs\n" . $herecurr);
		}

# * goes on variable not on type
		# (char*[ const])
		while ($line =~ m{(\($NonptrType(\s*(?:$Modifier\b\s*|\*\s*)+)\))}g) {
			#print "AA<$1>\n";
			my ($from, $to) = ($2, $2);

			# Should start with a space.
			$to =~ s/^(\S)/ $1/;
			# Should not end with a space.
			$to =~ s/\s+$//;
			# '*'s should not have spaces between.
			while ($to =~ s/\*\s+\*/\*\*/) {
			}

			#print "from<$from> to<$to>\n";
			if ($from ne $to) {
				ERROR("POINTER_LOCATION",
				      "\"(foo$from)\" should be \"(foo$to)\"\n" .  $herecurr);
			}
		}
		while ($line =~ m{(\b$NonptrType(\s*(?:$Modifier\b\s*|\*\s*)+)($Ident))}g) {
			#print "BB<$1>\n";
			my ($from, $to, $ident) = ($2, $2, $3);

			# Should start with a space.
			$to =~ s/^(\S)/ $1/;
			# Should not end with a space.
			$to =~ s/\s+$//;
			# '*'s should not have spaces between.
			while ($to =~ s/\*\s+\*/\*\*/) {
			}
			# Modifiers should have spaces.
			$to =~ s/(\b$Modifier$)/$1 /;

			#print "from<$from> to<$to> ident<$ident>\n";
			if ($from ne $to && $ident !~ /^$Modifier$/) {
				ERROR("POINTER_LOCATION",
				      "\"foo${from}bar\" should be \"foo${to}bar\"\n" .  $herecurr);
			}
		}

# # no BUG() or BUG_ON()
# 		if ($line =~ /\b(BUG|BUG_ON)\b/) {
# 			print "Try to use WARN_ON & Recovery code rather than BUG() or BUG_ON()\n";
# 			print "$herecurr";
# 			$clean = 0;
# 		}

		if ($line =~ /\bLINUX_VERSION_CODE\b/) {
			WARN("LINUX_VERSION_CODE",
			     "LINUX_VERSION_CODE should be avoided, code should be for the version to which it is merged\n" . $herecurr);
		}

# check for uses of printk_ratelimit
		if ($line =~ /\bprintk_ratelimit\s*\(/) {
			WARN("PRINTK_RATELIMITED",
"Prefer printk_ratelimited or pr_<level>_ratelimited to printk_ratelimit\n" . $herecurr);
		}

# printk should use KERN_* levels.  Note that follow on printk's on the
# same line do not need a level, so we use the current block context
# to try and find and validate the current printk.  In summary the current
# printk includes all preceding printk's which have no newline on the end.
# we assume the first bad printk is the one to report.
		if ($line =~ /\bprintk\((?!KERN_)\s*"/) {
			my $ok = 0;
			for (my $ln = $linenr - 1; $ln >= $first_line; $ln--) {
				#print "CHECK<$lines[$ln - 1]\n";
				# we have a preceding printk if it ends
				# with "\n" ignore it, else it is to blame
				if ($lines[$ln - 1] =~ m{\bprintk\(}) {
					if ($rawlines[$ln - 1] !~ m{\\n"}) {
						$ok = 1;
					}
					last;
				}
			}
			if ($ok == 0) {
				WARN("PRINTK_WITHOUT_KERN_LEVEL",
				     "printk() should include KERN_ facility level\n" . $herecurr);
			}
		}

		if ($line =~ /\bprintk\s*\(\s*KERN_([A-Z]+)/) {
			my $orig = $1;
			my $level = lc($orig);
			$level = "warn" if ($level eq "warning");
			my $level2 = $level;
			$level2 = "dbg" if ($level eq "debug");
			WARN("PREFER_PR_LEVEL",
			     "Prefer netdev_$level2(netdev, ... then dev_$level2(dev, ... then pr_$level(...  to printk(KERN_$orig ...\n" . $herecurr);
		}

		if ($line =~ /\bpr_warning\s*\(/) {
			WARN("PREFER_PR_LEVEL",
			     "Prefer pr_warn(... to pr_warning(...\n" . $herecurr);
		}

		if ($line =~ /\bdev_printk\s*\(\s*KERN_([A-Z]+)/) {
			my $orig = $1;
			my $level = lc($orig);
			$level = "warn" if ($level eq "warning");
			$level = "dbg" if ($level eq "debug");
			WARN("PREFER_DEV_LEVEL",
			     "Prefer dev_$level(... to dev_printk(KERN_$orig, ...\n" . $herecurr);
		}

# function brace can't be on same line, except for #defines of do while,
# or if closed on same line
		if (($line=~/$Type\s*$Ident\(.*\).*\s{/) and
		    !($line=~/\#\s*define.*do\s{/) and !($line=~/}/)) {
			ERROR("OPEN_BRACE",
			      "open brace '{' following function declarations go on the next line\n" . $herecurr);
		}

# open braces for enum, union and struct go on the same line.
		if ($line =~ /^.\s*{/ &&
		    $prevline =~ /^.\s*(?:typedef\s+)?(enum|union|struct)(?:\s+$Ident)?\s*$/) {
			ERROR("OPEN_BRACE",
			      "open brace '{' following $1 go on the same line\n" . $hereprev);
		}

# missing space after union, struct or enum definition
		if ($line =~ /^.\s*(?:typedef\s+)?(enum|union|struct)(?:\s+$Ident)?(?:\s+$Ident)?[=\{]/) {
		    WARN("SPACING",
			 "missing space after $1 definition\n" . $herecurr);
		}

# check for spacing round square brackets; allowed:
#  1. with a type on the left -- int [] a;
#  2. at the beginning of a line for slice initialisers -- [0...10] = 5,
#  3. inside a curly brace -- = { [0...10] = 5 }
		while ($line =~ /(.*?\s)\[/g) {
			my ($where, $prefix) = ($-[1], $1);
			if ($prefix !~ /$Type\s+$/ &&
			    ($where != 0 || $prefix !~ /^.\s+$/) &&
			    $prefix !~ /[{,]\s+$/) {
				ERROR("BRACKET_SPACE",
				      "space prohibited before open square bracket '['\n" . $herecurr);
			}
		}

# check for spaces between functions and their parentheses.
		while ($line =~ /($Ident)\s+\(/g) {
			my $name = $1;
			my $ctx_before = substr($line, 0, $-[1]);
			my $ctx = "$ctx_before$name";

			# Ignore those directives where spaces _are_ permitted.
			if ($name =~ /^(?:
				if|for|while|switch|return|case|
				volatile|__volatile__|
				__attribute__|format|__extension__|
				asm|__asm__)$/x)
			{

			# cpp #define statements have non-optional spaces, ie
			# if there is a space between the name and the open
			# parenthesis it is simply not a parameter group.
			} elsif ($ctx_before =~ /^.\s*\#\s*define\s*$/) {

			# cpp #elif statement condition may start with a (
			} elsif ($ctx =~ /^.\s*\#\s*elif\s*$/) {

			# If this whole things ends with a type its most
			# likely a typedef for a function.
			} elsif ($ctx =~ /$Type$/) {

			} else {
				WARN("SPACING",
				     "space prohibited between function name and open parenthesis '('\n" . $herecurr);
			}
		}

# check for whitespace before a non-naked semicolon
		if ($line =~ /^\+.*\S\s+;/) {
			CHK("SPACING",
			    "space prohibited before semicolon\n" . $herecurr);
		}

# Check operator spacing.
		if (!($line=~/\#\s*include/)) {
			my $ops = qr{
				<<=|>>=|<=|>=|==|!=|
				\+=|-=|\*=|\/=|%=|\^=|\|=|&=|
				=>|->|<<|>>|<|>|=|!|~|
				&&|\|\||,|\^|\+\+|--|&|\||\+|-|\*|\/|%|
				\?|:
			}x;
			my @elements = split(/($ops|;)/, $opline);
			my $off = 0;

			my $blank = copy_spacing($opline);

			for (my $n = 0; $n < $#elements; $n += 2) {
				$off += length($elements[$n]);

				# Pick up the preceding and succeeding characters.
				my $ca = substr($opline, 0, $off);
				my $cc = '';
				if (length($opline) >= ($off + length($elements[$n + 1]))) {
					$cc = substr($opline, $off + length($elements[$n + 1]));
				}
				my $cb = "$ca$;$cc";

				my $a = '';
				$a = 'V' if ($elements[$n] ne '');
				$a = 'W' if ($elements[$n] =~ /\s$/);
				$a = 'C' if ($elements[$n] =~ /$;$/);
				$a = 'B' if ($elements[$n] =~ /(\[|\()$/);
				$a = 'O' if ($elements[$n] eq '');
				$a = 'E' if ($ca =~ /^\s*$/);

				my $op = $elements[$n + 1];

				my $c = '';
				if (defined $elements[$n + 2]) {
					$c = 'V' if ($elements[$n + 2] ne '');
					$c = 'W' if ($elements[$n + 2] =~ /^\s/);
					$c = 'C' if ($elements[$n + 2] =~ /^$;/);
					$c = 'B' if ($elements[$n + 2] =~ /^(\)|\]|;)/);
					$c = 'O' if ($elements[$n + 2] eq '');
					$c = 'E' if ($elements[$n + 2] =~ /^\s*\\$/);
				} else {
					$c = 'E';
				}

				my $ctx = "${a}x${c}";

				my $at = "(ctx:$ctx)";

				my $ptr = substr($blank, 0, $off) . "^";
				my $hereptr = "$hereline$ptr\n";

				# Pull out the value of this operator.
				my $op_type = substr($curr_values, $off + 1, 1);

				# Get the full operator variant.
				my $opv = $op . substr($curr_vars, $off, 1);

				# Ignore operators passed as parameters.
				if ($op_type ne 'V' &&
				    $ca =~ /\s$/ && $cc =~ /^\s*,/) {

#				# Ignore comments
#				} elsif ($op =~ /^$;+$/) {

				# ; should have either the end of line or a space or \ after it
				} elsif ($op eq ';') {
					if ($ctx !~ /.x[WEBC]/ &&
					    $cc !~ /^\\/ && $cc !~ /^;/) {
						ERROR("SPACING",
						      "space required after that '$op' $at\n" . $hereptr);
					}

				# // is a comment
				} elsif ($op eq '//') {

				# No spaces for:
				#   ->
				#   :   when part of a bitfield
				} elsif ($op eq '->' || $opv eq ':B') {
					if ($ctx =~ /Wx.|.xW/) {
						ERROR("SPACING",
						      "spaces prohibited around that '$op' $at\n" . $hereptr);
					}

				# , must have a space on the right.
				} elsif ($op eq ',') {
					if ($ctx !~ /.x[WEC]/ && $cc !~ /^}/) {
						ERROR("SPACING",
						      "space required after that '$op' $at\n" . $hereptr);
					}

				# '*' as part of a type definition -- reported already.
				} elsif ($opv eq '*_') {
					#warn "'*' is part of type\n";

				# unary operators should have a space before and
				# none after.  May be left adjacent to another
				# unary operator, or a cast
				} elsif ($op eq '!' || $op eq '~' ||
					 $opv eq '*U' || $opv eq '-U' ||
					 $opv eq '&U' || $opv eq '&&U') {
					if ($ctx !~ /[WEBC]x./ && $ca !~ /(?:\)|!|~|\*|-|\&|\||\+\+|\-\-|\{)$/) {
						ERROR("SPACING",
						      "space required before that '$op' $at\n" . $hereptr);
					}
					if ($op eq '*' && $cc =~/\s*$Modifier\b/) {
						# A unary '*' may be const

					} elsif ($ctx =~ /.xW/) {
						ERROR("SPACING",
						      "space prohibited after that '$op' $at\n" . $hereptr);
					}

				# unary ++ and unary -- are allowed no space on one side.
				} elsif ($op eq '++' or $op eq '--') {
					if ($ctx !~ /[WEOBC]x[^W]/ && $ctx !~ /[^W]x[WOBEC]/) {
						ERROR("SPACING",
						      "space required one side of that '$op' $at\n" . $hereptr);
					}
					if ($ctx =~ /Wx[BE]/ ||
					    ($ctx =~ /Wx./ && $cc =~ /^;/)) {
						ERROR("SPACING",
						      "space prohibited before that '$op' $at\n" . $hereptr);
					}
					if ($ctx =~ /ExW/) {
						ERROR("SPACING",
						      "space prohibited after that '$op' $at\n" . $hereptr);
					}


				# << and >> may either have or not have spaces both sides
				} elsif ($op eq '<<' or $op eq '>>' or
					 $op eq '&' or $op eq '^' or $op eq '|' or
					 $op eq '+' or $op eq '-' or
					 $op eq '*' or $op eq '/' or
					 $op eq '%')
				{
					if ($ctx =~ /Wx[^WCE]|[^WCE]xW/) {
						ERROR("SPACING",
						      "need consistent spacing around '$op' $at\n" .
							$hereptr);
					}

				# A colon needs no spaces before when it is
				# terminating a case value or a label.
				} elsif ($opv eq ':C' || $opv eq ':L') {
					if ($ctx =~ /Wx./) {
						ERROR("SPACING",
						      "space prohibited before that '$op' $at\n" . $hereptr);
					}

				# All the others need spaces both sides.
				} elsif ($ctx !~ /[EWC]x[CWE]/) {
					my $ok = 0;

					# Ignore email addresses <foo@bar>
					if (($op eq '<' &&
					     $cc =~ /^\S+\@\S+>/) ||
					    ($op eq '>' &&
					     $ca =~ /<\S+\@\S+$/))
					{
					    	$ok = 1;
					}

					# Ignore ?:
					if (($opv eq ':O' && $ca =~ /\?$/) ||
					    ($op eq '?' && $cc =~ /^:/)) {
					    	$ok = 1;
					}

					if ($ok == 0) {
						ERROR("SPACING",
						      "spaces required around that '$op' $at\n" . $hereptr);
					}
				}
				$off += length($elements[$n + 1]);
			}
		}

# check for multiple assignments
		if ($line =~ /^.\s*$Lval\s*=\s*$Lval\s*=(?!=)/) {
			CHK("MULTIPLE_ASSIGNMENTS",
			    "multiple assignments should be avoided\n" . $herecurr);
		}

## # check for multiple declarations, allowing for a function declaration
## # continuation.
## 		if ($line =~ /^.\s*$Type\s+$Ident(?:\s*=[^,{]*)?\s*,\s*$Ident.*/ &&
## 		    $line !~ /^.\s*$Type\s+$Ident(?:\s*=[^,{]*)?\s*,\s*$Type\s*$Ident.*/) {
##
## 			# Remove any bracketed sections to ensure we do not
## 			# falsly report the parameters of functions.
## 			my $ln = $line;
## 			while ($ln =~ s/\([^\(\)]*\)//g) {
## 			}
## 			if ($ln =~ /,/) {
## 				WARN("MULTIPLE_DECLARATION",
##				     "declaring multiple variables together should be avoided\n" . $herecurr);
## 			}
## 		}

#need space before brace following if, while, etc
		if (($line =~ /\(.*\){/ && $line !~ /\($Type\){/) ||
		    $line =~ /do{/) {
			ERROR("SPACING",
			      "space required before the open brace '{'\n" . $herecurr);
		}

# closing brace should have a space following it when it has anything
# on the line
		if ($line =~ /}(?!(?:,|;|\)))\S/) {
			ERROR("SPACING",
			      "space required after that close brace '}'\n" . $herecurr);
		}

# check spacing on square brackets
		if ($line =~ /\[\s/ && $line !~ /\[\s*$/) {
			ERROR("SPACING",
			      "space prohibited after that open square bracket '['\n" . $herecurr);
		}
		if ($line =~ /\s\]/) {
			ERROR("SPACING",
			      "space prohibited before that close square bracket ']'\n" . $herecurr);
		}

# check spacing on parentheses
		if ($line =~ /\(\s/ && $line !~ /\(\s*(?:\\)?$/ &&
		    $line !~ /for\s*\(\s+;/) {
			ERROR("SPACING",
			      "space prohibited after that open parenthesis '('\n" . $herecurr);
		}
		if ($line =~ /(\s+)\)/ && $line !~ /^.\s*\)/ &&
		    $line !~ /for\s*\(.*;\s+\)/ &&
		    $line !~ /:\s+\)/) {
			ERROR("SPACING",
			      "space prohibited before that close parenthesis ')'\n" . $herecurr);
		}

#goto labels aren't indented, allow a single space however
		if ($line=~/^.\s+[A-Za-z\d_]+:(?![0-9]+)/ and
		   !($line=~/^. [A-Za-z\d_]+:/) and !($line=~/^.\s+default:/)) {
			WARN("INDENTED_LABEL",
			     "labels should not be indented\n" . $herecurr);
		}

# Return is not a function.
		if (defined($stat) && $stat =~ /^.\s*return(\s*)(\(.*);/s) {
			my $spacing = $1;
			my $value = $2;

			# Flatten any parentheses
			$value =~ s/\(/ \(/g;
			$value =~ s/\)/\) /g;
			while ($value =~ s/\[[^\[\]]*\]/1/ ||
			       $value !~ /(?:$Ident|-?$Constant)\s*
					     $Compare\s*
					     (?:$Ident|-?$Constant)/x &&
			       $value =~ s/\([^\(\)]*\)/1/) {
			}
#print "value<$value>\n";
			if ($value =~ /^\s*(?:$Ident|-?$Constant)\s*$/) {
				ERROR("RETURN_PARENTHESES",
				      "return is not a function, parentheses are not required\n" . $herecurr);

			} elsif ($spacing !~ /\s+/) {
				ERROR("SPACING",
				      "space required before the open parenthesis '('\n" . $herecurr);
			}
		}
# Return of what appears to be an errno should normally be -'ve
		if ($line =~ /^.\s*return\s*(E[A-Z]*)\s*;/) {
			my $name = $1;
			if ($name ne 'EOF' && $name ne 'ERROR') {
				WARN("USE_NEGATIVE_ERRNO",
				     "return of an errno should typically be -ve (return -$1)\n" . $herecurr);
			}
		}

# Need a space before open parenthesis after if, while etc
		if ($line=~/\b(if|while|for|switch)\(/) {
			ERROR("SPACING", "space required before the open parenthesis '('\n" . $herecurr);
		}

# Check for illegal assignment in if conditional -- and check for trailing
# statements after the conditional.
		if ($line =~ /do\s*(?!{)/) {
			($stat, $cond, $line_nr_next, $remain_next, $off_next) =
				ctx_statement_block($linenr, $realcnt, 0)
					if (!defined $stat);
			my ($stat_next) = ctx_statement_block($line_nr_next,
						$remain_next, $off_next);
			$stat_next =~ s/\n./\n /g;
			##print "stat<$stat> stat_next<$stat_next>\n";

			if ($stat_next =~ /^\s*while\b/) {
				# If the statement carries leading newlines,
				# then count those as offsets.
				my ($whitespace) =
					($stat_next =~ /^((?:\s*\n[+-])*\s*)/s);
				my $offset =
					statement_rawlines($whitespace) - 1;

				$suppress_whiletrailers{$line_nr_next +
								$offset} = 1;
			}
		}
		if (!defined $suppress_whiletrailers{$linenr} &&
		    $line =~ /\b(?:if|while|for)\s*\(/ && $line !~ /^.\s*#/) {
			my ($s, $c) = ($stat, $cond);

			if ($c =~ /\bif\s*\(.*[^<>!=]=[^=].*/s) {
				ERROR("ASSIGN_IN_IF",
				      "do not use assignment in if condition\n" . $herecurr);
			}

			# Find out what is on the end of the line after the
			# conditional.
			substr($s, 0, length($c), '');
			$s =~ s/\n.*//g;
			$s =~ s/$;//g; 	# Remove any comments
			if (length($c) && $s !~ /^\s*{?\s*\\*\s*$/ &&
			    $c !~ /}\s*while\s*/)
			{
				# Find out how long the conditional actually is.
				my @newlines = ($c =~ /\n/gs);
				my $cond_lines = 1 + $#newlines;
				my $stat_real = '';

				$stat_real = raw_line($linenr, $cond_lines)
							. "\n" if ($cond_lines);
				if (defined($stat_real) && $cond_lines > 1) {
					$stat_real = "[...]\n$stat_real";
				}

				ERROR("TRAILING_STATEMENTS",
				      "trailing statements should be on next line\n" . $herecurr . $stat_real);
			}
		}

# Check for bitwise tests written as boolean
		if ($line =~ /
			(?:
				(?:\[|\(|\&\&|\|\|)
				\s*0[xX][0-9]+\s*
				(?:\&\&|\|\|)
			|
				(?:\&\&|\|\|)
				\s*0[xX][0-9]+\s*
				(?:\&\&|\|\||\)|\])
			)/x)
		{
			WARN("HEXADECIMAL_BOOLEAN_TEST",
			     "boolean test with hexadecimal, perhaps just 1 \& or \|?\n" . $herecurr);
		}

# if and else should not have general statements after it
		if ($line =~ /^.\s*(?:}\s*)?else\b(.*)/) {
			my $s = $1;
			$s =~ s/$;//g; 	# Remove any comments
			if ($s !~ /^\s*(?:\sif|(?:{|)\s*\\?\s*$)/) {
				ERROR("TRAILING_STATEMENTS",
				      "trailing statements should be on next line\n" . $herecurr);
			}
		}
# if should not continue a brace
		if ($line =~ /}\s*if\b/) {
			ERROR("TRAILING_STATEMENTS",
			      "trailing statements should be on next line\n" .
				$herecurr);
		}
# case and default should not have general statements after them
		if ($line =~ /^.\s*(?:case\s*.*|default\s*):/g &&
		    $line !~ /\G(?:
			(?:\s*$;*)(?:\s*{)?(?:\s*$;*)(?:\s*\\)?\s*$|
			\s*return\s+
		    )/xg)
		{
			ERROR("TRAILING_STATEMENTS",
			      "trailing statements should be on next line\n" . $herecurr);
		}

		# Check for }<nl>else {, these must be at the same
		# indent level to be relevant to each other.
		if ($prevline=~/}\s*$/ and $line=~/^.\s*else\s*/ and
						$previndent == $indent) {
			ERROR("ELSE_AFTER_BRACE",
			      "else should follow close brace '}'\n" . $hereprev);
		}

		if ($prevline=~/}\s*$/ and $line=~/^.\s*while\s*/ and
						$previndent == $indent) {
			my ($s, $c) = ctx_statement_block($linenr, $realcnt, 0);

			# Find out what is on the end of the line after the
			# conditional.
			substr($s, 0, length($c), '');
			$s =~ s/\n.*//g;

			if ($s =~ /^\s*;/) {
				ERROR("WHILE_AFTER_BRACE",
				      "while should follow close brace '}'\n" . $hereprev);
			}
		}

#CamelCase
		while ($line =~ m{($Constant|$Lval)}g) {
			my $var = $1;
			if ($var !~ /$Constant/ &&
			    $var =~ /[A-Z]\w*[a-z]|[a-z]\w*[A-Z]/ &&
			    $var !~ /^Page[A-Z]/ &&
			    !defined $camelcase{$var}) {
				$camelcase{$var} = 1;
				WARN("CAMELCASE",
				     "Avoid CamelCase: <$var>\n" . $herecurr);
			}
		}

#no spaces allowed after \ in define
		if ($line=~/\#\s*define.*\\\s$/) {
			WARN("WHITESPACE_AFTER_LINE_CONTINUATION",
			     "Whitepspace after \\ makes next lines useless\n" . $herecurr);
		}

#warn if <asm/foo.h> is #included and <linux/foo.h> is available (uses RAW line)
		if ($tree && $rawline =~ m{^.\s*\#\s*include\s*\<asm\/(.*)\.h\>}) {
			my $file = "$1.h";
			my $checkfile = "include/linux/$file";
			if (-f "$root/$checkfile" &&
			    $realfile ne $checkfile &&
			    $1 !~ /$allowed_asm_includes/)
			{
				if ($realfile =~ m{^arch/}) {
					CHK("ARCH_INCLUDE_LINUX",
					    "Consider using #include <linux/$file> instead of <asm/$file>\n" . $herecurr);
				} else {
					WARN("INCLUDE_LINUX",
					     "Use #include <linux/$file> instead of <asm/$file>\n" . $herecurr);
				}
			}
		}

# multi-statement macros should be enclosed in a do while loop, grab the
# first statement and ensure its the whole macro if its not enclosed
# in a known good container
		if ($realfile !~ m@/vmlinux.lds.h$@ &&
		    $line =~ /^.\s*\#\s*define\s*$Ident(\()?/) {
			my $ln = $linenr;
			my $cnt = $realcnt;
			my ($off, $dstat, $dcond, $rest);
			my $ctx = '';
			($dstat, $dcond, $ln, $cnt, $off) =
				ctx_statement_block($linenr, $realcnt, 0);
			$ctx = $dstat;
			#print "dstat<$dstat> dcond<$dcond> cnt<$cnt> off<$off>\n";
			#print "LINE<$lines[$ln-1]> len<" . length($lines[$ln-1]) . "\n";

			$dstat =~ s/^.\s*\#\s*define\s+$Ident(?:\([^\)]*\))?\s*//;
			$dstat =~ s/$;//g;
			$dstat =~ s/\\\n.//g;
			$dstat =~ s/^\s*//s;
			$dstat =~ s/\s*$//s;

			# Flatten any parentheses and braces
			while ($dstat =~ s/\([^\(\)]*\)/1/ ||
			       $dstat =~ s/\{[^\{\}]*\}/1/ ||
			       $dstat =~ s/\[[^\[\]]*\]/1/)
			{
			}

			# Flatten any obvious string concatentation.
			while ($dstat =~ s/("X*")\s*$Ident/$1/ ||
			       $dstat =~ s/$Ident\s*("X*")/$1/)
			{
			}

			my $exceptions = qr{
				$Declare|