Add BSSPACE and COLONPLUS lint warnings.

Changes

@@ -12,6 +12,8 @@ The contributors that suggested a given feature are shown in []. Thanks!
 
 ****  Add error when driving input-only modport.
 
+****  Add BSSPACE and COLONPLUS lint warnings.
+
 ****  Fix false unused warning on interfaces, bug1241. [Laurens van Dam]
 
 

bin/verilator

@@ -1251,11 +1251,11 @@ directives in the source, i.e. the warning will still not be printed.
 =item -Wno-lint
 
 Disable all lint related warning messages, and all style warnings.  This is
-equivalent to "-Wno-ALWCOMBORDER -Wno-CASEINCOMPLETE -Wno-CASEOVERLAP
--Wno-CASEX -Wno-CASEWITHX -Wno-CMPCONST -Wno-ENDLABEL -Wno-IMPLICIT
--Wno-LITENDIAN -Wno-PINCONNECTEMPTY -Wno-PINMISSING -Wno-SYNCASYNCNET
--Wno-UNDRIVEN -Wno-UNSIGNED -Wno-UNUSED -Wno-WIDTH" plus the list shown for
-Wno-style.
+equivalent to "-Wno-ALWCOMBORDER -Wno-BSSPACE -Wno-CASEINCOMPLETE
+-Wno-CASEOVERLAP -Wno-CASEX -Wno-CASEWITHX -Wno-CMPCONST -Wno-COLONPLUS
+-Wno-ENDLABEL -Wno-IMPLICIT -Wno-LITENDIAN -Wno-PINCONNECTEMPTY
+-Wno-PINMISSING -Wno-SYNCASYNCNET -Wno-UNDRIVEN -Wno-UNSIGNED -Wno-UNUSED
+-Wno-WIDTH" plus the list shown for Wno-style.
 
 It is strongly recommended you cleanup your code rather than using this
 option, it is only intended to be use when running test-cases of code
@@ -1284,10 +1284,10 @@ Enables the specified warning message.
 
 Enable all lint related warning messages (note by default they are already
 enabled), but do not affect style messages.  This is equivalent to
-"-Wwarn-ALWCOMBORDER -Wwarn-CASEINCOMPLETE -Wwarn-CASEOVERLAP -Wwarn-CASEX
--Wwarn-CASEWITHX -Wwarn-CMPCONST -Wwarn-ENDLABEL -Wwarn-IMPLICIT
--Wwarn-LITENDIAN -Wwarn-PINMISSING -Wwarn-REALCVT -Wwarn-UNSIGNED
--Wwarn-WIDTH".
+"-Wwarn-ALWCOMBORDER -Wwarn-BSSPACE -Wwarn-CASEINCOMPLETE
+-Wwarn-CASEOVERLAP -Wwarn-CASEX -Wwarn-CASEWITHX -Wwarn-CMPCONST
+-Wwarn-COLONPLUS -Wwarn-ENDLABEL -Wwarn-IMPLICIT -Wwarn-LITENDIAN
+-Wwarn-PINMISSING -Wwarn-REALCVT -Wwarn-UNSIGNED -Wwarn-WIDTH".
 
 =item -Wwarn-style
 
@@ -3081,6 +3081,17 @@ generally unrolls small loops.  You may want to try increasing
 --unroll-count (and occasionally --unroll-stmts) which will raise the small
 loop bar to avoid this error.
 
+=item BSSPACE
+
+Warns that a backslash is followed by a space then a newline. Likely the
+intent was to have a backslash directly followed by a newline (e.g. when
+making a `define) and there's accidentally whitespace at the end of the
+line.  If the space is not accidental, suggest removing the backslash in
+the code as it serves no function.
+
+Ignoring this warning will only suppress the lint check, it will simulate
+correctly.
+
 =item CASEINCOMPLETE
 
 Warns that inside a case statement there is a stimulus pattern for which
@@ -3120,6 +3131,15 @@ instead intended is to use a casez with C<?>.
 Ignoring this warning will only suppress the lint check, it will simulate
 correctly.
 
+=item COLONPLUS
+
+Warns that a :+ is seen. Likely the intent was to use +: to select a range
+of bits. If the intent was a range that is explicitly positive, suggest
+adding a space, e.g. use ": +".
+
+Ignoring this warning will only suppress the lint check, it will simulate
+correctly.
+
 =item CDCRSTLOGIC
 
 With --cdc only, warns that asynchronous flop reset terms come from other

src/V3Error.h

@@ -61,6 +61,7 @@ public:
 	BLKANDNBLK,	// Blocked and non-blocking assignments to same variable
 	BLKLOOPINIT,	// Delayed assignment to array inside for loops
 	BLKSEQ,		// Blocking assignments in sequential block
+	BSSPACE,	// Backslash space
 	CASEINCOMPLETE,	// Case statement has missing values
 	CASEOVERLAP,	// Case statements overlap
 	CASEWITHX,	// Case with X values
@@ -68,6 +69,7 @@ public:
 	CDCRSTLOGIC,	// Logic in async reset path
 	CLKDATA,        // Clock used as data
 	CMPCONST,	// Comparison is constant due to limited range
+	COLONPLUS,	// :+ instead of +:
 	COMBDLY,	// Combinatorial delayed assignment
 	DEFPARAM,	// Style: Defparam
 	DECLFILENAME,	// Declaration doesn't match filename
@@ -125,9 +127,9 @@ public:
 	    // Warnings
 	    " EC_FIRST_WARN",
 	    "ALWCOMBORDER", "ASSIGNDLY", "ASSIGNIN",
-	    "BLKANDNBLK", "BLKLOOPINIT", "BLKSEQ",
+	    "BLKANDNBLK", "BLKLOOPINIT", "BLKSEQ", "BSSPACE",
 	    "CASEINCOMPLETE", "CASEOVERLAP", "CASEWITHX", "CASEX", "CDCRSTLOGIC", "CLKDATA",
-	    "CMPCONST", "COMBDLY", "DEFPARAM", "DECLFILENAME",
+	    "CMPCONST", "COLONPLUS", "COMBDLY", "DEFPARAM", "DECLFILENAME",
 	    "ENDLABEL", "GENCLK",
 	    "IFDEPTH", "IMPERFECTSCH", "IMPLICIT", "IMPURE",
 	    "INCABSPATH", "INITIALDLY",
@@ -158,9 +160,11 @@ public:
 
     // Warnings that are lint only
     bool lintError() const { return ( m_e==ALWCOMBORDER
+				      || m_e==BSSPACE
 				      || m_e==CASEINCOMPLETE || m_e==CASEOVERLAP
 				      || m_e==CASEWITHX || m_e==CASEX
 				      || m_e==CMPCONST
+				      || m_e==COLONPLUS
 				      || m_e==ENDLABEL
 				      || m_e==IMPLICIT
 				      || m_e==LITENDIAN

src/V3PreLex.l

@@ -70,7 +70,6 @@ wsn		[ \t\f]
 crnl		[\r]*[\n]
 quote		[\"]
 tickquote	[`][\"]
-backslash	[\\]
 /* Where we use symb/symbdef, we must also look for a `` join */
 /* Note in the preprocessor \ESCaped is *not* always special; mantis1537/bug441 */
 symb		([a-zA-Z_][a-zA-Z0-9_$]*|\\[^ \t\f\r\n]+)
@@ -110,8 +109,9 @@ drop		[\032]
 <STRMODE>{crnl}		{ linenoInc(); yyerrorf("Unterminated string"); BEGIN(INITIAL); }
 <STRMODE>{word}		{ yymore(); }
 <STRMODE>[^\"\\]	{ yymore(); }
-<STRMODE>{backslash}{crnl}	{ linenoInc(); yymore(); }
-<STRMODE>{backslash}.	{ yymore(); }
+<STRMODE>[\\]{crnl}	{ linenoInc(); yymore(); }
+<STRMODE>[\\]{wsn}+{crnl}  { yyless(1); LEXP->curFilelinep()->v3warn(BSSPACE, "Backslash followed by whitespace, perhaps the whitespace is accidental?"); }
+<STRMODE>[\\].		{ yymore(); }
 <STRMODE>{quote} 	{ yy_pop_state();
 			  if (LEXP->m_parenLevel || LEXP->m_defQuote) { LEXP->m_defQuote=false; appendDefValue(yytext,yyleng); yyleng=0; }
 			  else return (VP_STRING); }
@@ -144,7 +144,7 @@ drop		[\032]
 <INCMODE><<EOF>>	{ linenoInc(); yyerrorf("EOF in unterminated include filename"); yyleng=0; yyterminate(); }
 <INCMODE>{crnl}		{ linenoInc(); yyerrorf("Unterminated include filename"); BEGIN(INITIAL); }
 <INCMODE>[^\>\\]	{ yymore(); }
-<INCMODE>{backslash}.	{ yymore(); }
+<INCMODE>[\\].		{ yymore(); }
 <INCMODE>[\>]	 	{ yy_pop_state(); return VP_STRING; }
 
 	/* Reading definition formal parenthesis (or not) to begin formal arguments */
@@ -162,6 +162,7 @@ drop		[\032]
 <DEFFORM>{drop}		{ }
 <DEFFORM><<EOF>>	{ linenoInc(); yy_pop_state(); yyerrorf("Unterminated ( in define formal arguments."); yyleng=0; return VP_DEFFORM; }
 <DEFFORM>{crnl}		{ linenoInc(); appendDefValue((char*)"\n",1); } /* Include return so can maintain output line count */
+<DEFFORM>[\\]{wsn}+{crnl}  { yyless(1); LEXP->curFilelinep()->v3warn(BSSPACE, "Backslash followed by whitespace, perhaps the whitespace is accidental?"); }
 <DEFFORM>[\\]{crnl}	{ linenoInc(); appendDefValue((char*)"\\\n",2); } /* Include return so can maintain output line count */
 <DEFFORM>{quote}	{ LEXP->m_defQuote=true; yy_push_state(STRMODE); yymore(); }  /* Legal only in default values */
 <DEFFORM>"`\\`\""	{ appendDefValue(yytext,yyleng); }  /* Maybe illegal, otherwise in default value */
@@ -179,6 +180,7 @@ drop		[\032]
 <DEFVAL>{drop}		{ }
 <DEFVAL><<EOF>>		{ linenoInc(); yy_pop_state(); yytext=(char*)"\n"; yyleng=1; return (VP_DEFVALUE); } /* Technically illegal, but people complained */
 <DEFVAL>{crnl}		{ linenoInc(); yy_pop_state(); yytext=(char*)"\n"; yyleng=1; return (VP_DEFVALUE); }
+<DEFVAL>[\\]{wsn}+{crnl}  { yyless(1); LEXP->curFilelinep()->v3warn(BSSPACE, "Backslash followed by whitespace, perhaps the whitespace is accidental?"); }
 <DEFVAL>[\\]{crnl}	{ linenoInc(); appendDefValue((char*)"\\\n",2); } /* Return, AND \ is part of define value */
 <DEFVAL>{quote}		{ LEXP->m_defQuote=true; yy_push_state(STRMODE); yymore(); }
 <DEFVAL>[^\/\*\n\r\\\"]+	|
@@ -189,6 +191,7 @@ drop		[\032]
 	/* - if no \{crnl} ending then the comment belongs to the next line, as a non-embedded comment */
 	/* - if all but (say) 3rd line is missing \ then it's indeterminate */
 <DEFCMT>"*/"		{ yy_pop_state(); appendDefValue(yytext,yyleng); }
+<DEFCMT>[\\]{wsn}+{crnl}  { yyless(1); LEXP->curFilelinep()->v3warn(BSSPACE, "Backslash followed by whitespace, perhaps the whitespace is accidental?"); }
 <DEFCMT>[\\]{crnl}	{ linenoInc(); LEXP->m_defCmtSlash=true;
 	 		  appendDefValue(yytext,yyleng-2); appendDefValue((char*)"\n",1); }  /* Return but not \ */
 <DEFCMT>{crnl}		{ linenoInc(); yymore(); if (LEXP->m_defCmtSlash) yyerrorf("One line of /* ... */ is missing \\ before newline");

src/verilog.l

@@ -783,6 +783,9 @@ vnum	{vnum1}|{vnum2}|{vnum3}|{vnum4}|{vnum5}
   "+:"			{ FL; return yP_PLUSCOLON; }
   "-:"			{ FL; return yP_MINUSCOLON; }
   ".*"			{ FL; return yP_DOTSTAR; }
+  ":+"			{ FL; yyless(1);
+                          PARSEP->fileline()->v3warn(COLONPLUS, "Perhaps instead of ':+' the intent was '+:'?");
+                          return ':'; }
 }
 
   /* SystemVerilog Operators */

test_regress/t/t_lint_bsspace_bad.pl

@@ -0,0 +1,24 @@
+#!/usr/bin/perl
+if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); die; }
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# Copyright 2003 by Wilson Snyder. This program is free software; you can
+# redistribute it and/or modify it under the terms of either the GNU
+# Lesser General Public License Version 3 or the Perl Artistic License
+# Version 2.0.
+
+$Self->{vlt} or $Self->skip("Verilator only test");
+
+compile (
+    verilator_flags2 => ["--lint-only"],
+    verilator_make_gcc => 0,
+    make_top_shell => 0,
+    make_main => 0,
+    fails => 1,
+    expect=>
+'%Warning-BSSPACE: t/t_lint_bsspace_bad.v:\d+: Backslash followed by whitespace, perhaps the whitespace is accidental\?
+.*%Error: Exiting due to.*',
+    );
+
+ok(1);
+1;

test_regress/t/t_lint_bsspace_bad.v

@@ -0,0 +1,13 @@
+// DESCRIPTION: Verilator: Verilog Test module
+//
+// This file ONLY is placed into the Public Domain, for any use,
+// without warranty, 2017 by Wilson Snyder.
+
+// Fake binary character here '', so is treated as binary and
+// don't get whitespace violation.
+
+`define FOO   blak \ 
+   blak
+
+module t;
+endmodule

test_regress/t/t_lint_colonplus_bad.pl

@@ -0,0 +1,25 @@
+#!/usr/bin/perl
+if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); die; }
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# Copyright 2003 by Wilson Snyder. This program is free software; you can
+# redistribute it and/or modify it under the terms of either the GNU
+# Lesser General Public License Version 3 or the Perl Artistic License
+# Version 2.0.
+
+$Self->{vlt} or $Self->skip("Verilator only test");
+
+compile (
+    verilator_flags2 => ["--lint-only"],
+    verilator_make_gcc => 0,
+    make_top_shell => 0,
+    make_main => 0,
+    fails => 1,
+    expect=>
+q{%Warning-COLONPLUS: t/t_lint_colonplus_bad.v:\d+: Perhaps instead of ':\+' the intent was '\+:'\?
+%Warning-COLONPLUS: Use .*
+.*%Error: Exiting due to.*},
+    );
+
+ok(1);
+1;

test_regress/t/t_lint_colonplus_bad.v

@@ -0,0 +1,14 @@
+// DESCRIPTION: Verilator: Verilog Test module
+//
+// This file ONLY is placed into the Public Domain, for any use,
+// without warranty, 2017 by Wilson Snyder.
+
+module t (/*AUTOARG*/
+   // Outputs
+   z
+   );
+
+   reg [3:0] r = 4'b1010;
+   output [2:1] z = r[2 :+ 1];
+
+endmodule