--- a/CHANGES	Thu Dec 15 23:53:13 2016 -0500
+++ b/CHANGES	Tue Aug 01 14:51:04 2017 -0400
@@ -1,4 +1,11 @@
 release [pending]
+   - Abort on line numbering or column numbering overflow. Line
+     numbers are limited to values that fit in "unsigned int". Also
+     reject input lines longer than 2^32-1 characters. It seems
+     reasonable to presume that any input that violates these
+     constraints is someone screwing around and not a serious attempt
+     to compile or preprocess anything useful. Done in response to
+     n2129, but without getting into any of the silliness found there.
    - Recognize __ia64__ for IA64 builds.
 
 release 0.5.2 (20160904)

--- a/directive.c	Thu Dec 15 23:53:13 2016 -0500
+++ b/directive.c	Tue Aug 01 14:51:04 2017 -0400
@@ -114,7 +114,7 @@
 
 	pos = strcspn(line, ws);
 	if (line[pos] != '\0') {
-		p2->column += pos;
+		place_addcolumns(p2, pos);
 		complain(p2, "Garbage after %s argument", what);
 		complain_fail();
 		line[pos] = '\0';
@@ -348,13 +348,13 @@
 		argpos = pos;
 		pos = pos + strcspn(line+pos, "()");
 		if (line[pos] == '(') {
-			p2->column += pos;
+			place_addcolumns(p2, pos);
 			complain(p2, "Left parenthesis in macro parameters");
 			complain_fail();
 			return;
 		}
 		if (line[pos] != ')') {
-			p2->column += pos;
+			place_addcolumns(p2, pos);
 			complain(p2, "Unclosed macro parameter list");
 			complain_fail();
 			return;
@@ -378,10 +378,10 @@
 	pos += strspn(line+pos, ws);
 
 	p3 = *p2;
-	p3.column += argpos;
+	place_addcolumns(&p3, argpos);
 
 	p4 = *p2;
-	p4.column += pos;
+	place_addcolumns(&p4, pos);
 
 	if (argpos) {
 		debuglog(&lp->current, "Defining %s()", line);
@@ -490,7 +490,8 @@
 	errno = 0;
 	val = strtoul(text, &moretext, 10);
 	if (errno) {
-		complain(&lp->current, "No line number in #line directive");
+		complain(&lp->current,
+			 "Invalid line number in #line directive");
 		goto fail;
 	}
 #if UINT_MAX < ULONG_MAX
@@ -502,7 +503,7 @@
 #endif
 	moretext += strspn(moretext, ws);
 	moretextlen = strlen(moretext);
-	lp->current.column += (moretext - text);
+	place_addcolumns(&lp->current, moretext - text);
 
 	if (moretextlen > 2 &&
 	    moretext[0] == '"' && moretext[moretextlen-1] == '"') {
@@ -610,7 +611,7 @@
 				return;
 			}
 			skip = len + strspn(line+len, ws);
-			p2.column += skip;
+			place_addcolumns(&p2, skip);
 			line += skip;
 
 			len = strlen(line);
@@ -667,10 +668,10 @@
 			pos++;
 		}
 		if (line[pos] == '\n') {
-			p2.line++;
+			place_addlines(&p2, 1);
 			p2.column = 0;
 		} else {
-			p2.column++;
+			place_addcolumns(&p2, 1);
 		}
 	}
 
@@ -692,13 +693,13 @@
 	if (len > 0 && line[0] == '#') {
 		skip = 1 + strspn(line + 1, ws);
 		assert(skip <= len);
-		lp->current.column += skip;
+		place_addcolumns(&lp->current, skip);
 		assert(line[len] == '\0');
 		directive_gotdirective(lp, line+skip /*, length = len-skip */);
-		lp->current.column += len-skip;
+		place_addcolumns(&lp->current, len-skip);
 	} else if (ifstate->curtrue) {
 		macro_sendline(&lp->current, line, len);
-		lp->current.column += len;
+		place_addcolumns(&lp->current, len);
 	}
 }
 

--- a/eval.c	Thu Dec 15 23:53:13 2016 -0500
+++ b/eval.c	Tue Aug 01 14:51:04 2017 -0400
@@ -708,29 +708,29 @@
 	while (expr[pos] != '\0') {
 		len = strspn(expr+pos, ws);
 		pos += len;
-		p->column += len;
+		place_addcolumns(p, len);
 		/* trailing whitespace is supposed to have been pruned */
 		assert(expr[pos] != '\0');
 		if (check_word(p, expr, pos, &len)) {
 			pos += len;
-			p->column += len;
+			place_addcolumns(p, len);
 			continue;
 		}
 		if (check_tokens_2(p, expr, pos)) {
 			pos += 2;
-			p->column += 2;
+			place_addcolumns(p, 2);
 			continue;
 		}
 		if (check_tokens_1(p, expr, pos)) {
 			pos++;
-			p->column++;
+			place_addcolumns(p, 1);
 			continue;
 		}
 		complain(p, "Invalid character %u in #if-expression",
 			 (unsigned char)expr[pos]);
 		complain_fail();
 		pos++;
-		p->column++;
+		place_addcolumns(p, 1);
 	}
 	token(p, T_EOF, 0);
 }

--- a/files.c	Thu Dec 15 23:53:13 2016 -0500
+++ b/files.c	Tue Aug 01 14:51:04 2017 -0400
@@ -163,6 +163,10 @@
 	for (i=start; i<limit; i++) {
 		if (buf[i] == '\n') {
 			count++;
+			if (count == 0) {
+				/* just return the max and error downstream */
+				return count - 1;
+			}
 		}
 	}
 	return count;
@@ -209,6 +213,12 @@
 				/* need bigger buffer */
 				buf = dorealloc(buf, bufmax, bufmax*2);
 				bufmax = bufmax*2;
+				/* just in case someone's screwing around */
+				if (bufmax > 0xffffffff) {
+					complain(&places.current,
+						 "Input line too long");
+					die();
+				}
 			}
 
 			if (ateof) {
@@ -231,7 +241,7 @@
 				/* eof in middle of line */
 				ateof = true;
 				ptmp = places.current;
-				ptmp.column += bufend - linestart;
+				place_addcolumns(&ptmp, bufend - linestart);
 				if (buf[bufend - 1] == '\n') {
 					complain(&ptmp, "Unclosed comment");
 					complain_fail();
@@ -257,7 +267,7 @@
 		assert(buf[lineend] == '\n');
 		buf[lineend] = '\0';
 		nextlinestart = lineend+1;
-		places.nextline.line++;
+		place_addlines(&places.nextline, 1);
 
 		/* check for CR/NL */
 		if (lineend > 0 && buf[lineend-1] == '\r') {
@@ -284,7 +294,8 @@
 		assert(buf[lineend] == '\0');
 
 		/* count how many commented-out newlines we swallowed */
-		places.nextline.line += countnls(buf, linestart, lineend);
+		place_addlines(&places.nextline,
+			       countnls(buf, linestart, lineend));
 
 		/* process the line (even if it's empty) */
 		directive_gotline(&places, buf+linestart, lineend-linestart);

--- a/macro.c	Thu Dec 15 23:53:13 2016 -0500
+++ b/macro.c	Tue Aug 01 14:51:04 2017 -0400
@@ -523,7 +523,7 @@
 	while (params != NULL) {
 		len = strspn(params, ws);
 		params += len;
-		p->column += len;
+		place_addcolumns(p, len);
 		s = strchr(params, ',');
 		if (s) {
 			len = s-params;
@@ -541,7 +541,7 @@
 			stringarray_add(&m->params, param, NULL);
 		}
 		params = s;
-		p->column += len;
+		place_addcolumns(p, len);
 	}
 }
 

--- a/main.c	Thu Dec 15 23:53:13 2016 -0500
+++ b/main.c	Tue Aug 01 14:51:04 2017 -0400
@@ -155,7 +155,7 @@
 
 	if (val) {
 		p2 = *p;
-		p2.column += strlen(str);
+		place_addcolumns(&p2, strlen(str));
 	} else {
 		place_setbuiltin(&p2, 1);
 	}

--- a/place.c	Thu Dec 15 23:53:13 2016 -0500
+++ b/place.c	Tue Aug 01 14:51:04 2017 -0400
@@ -193,6 +193,34 @@
 	p->column = 1;
 }
 
+void
+place_addcolumns(struct place *p, unsigned cols)
+{
+	unsigned newcol;
+
+	newcol = p->column + cols;
+	if (newcol < p->column) {
+		/* overflow (use the old place to complain) */
+		complain(p, "Column numbering overflow");
+		die();
+	}
+	p->column = newcol;
+}
+
+void
+place_addlines(struct place *p, unsigned lines)
+{
+	unsigned nextline;
+
+	nextline = p->line + lines;
+	if (nextline < p->line) {
+		/* overflow (use the old place to complain) */
+		complain(p, "Line numbering overflow");
+		die();
+	}
+	p->line = nextline;
+}
+
 const char *
 place_getname(const struct place *p)
 {

--- a/place.h	Thu Dec 15 23:53:13 2016 -0500
+++ b/place.h	Tue Aug 01 14:51:04 2017 -0400
@@ -53,6 +53,9 @@
 void place_setcommandline(struct place *p, unsigned word, unsigned column);
 void place_setfilestart(struct place *p, const struct placefile *pf);
 
+void place_addcolumns(struct place *, unsigned cols);
+void place_addlines(struct place *, unsigned lines);
+
 const char *place_getname(const struct place *);
 const char *place_getparsedir(const struct place *incplace);
 bool place_eq(const struct place *, const struct place *);