From c6f7989176b9da3b977f397ac4f20bc2f86dec1b Mon Sep 17 00:00:00 2001
From: Ori Bernstein <ori@eigenstate.org>
Date: Sun, 26 Apr 2020 09:32:42 -0700
Subject: [PATCH] copy all the tokens from the tokenrows with a paste.

if we do 'CAT(foo bar, baz quux)', the resulting token row
should have 3 tokens: 'foo', 'barbaz', 'quux'.

tested by jonasa, rebuilding /sys/src, perl, netsurf, and nuklear.
---
 sys/src/cmd/cpp/macro.c | 16 +++++++++++-----
 sys/src/cmd/cpp/test.c  |  5 ++++-
 2 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/sys/src/cmd/cpp/macro.c b/sys/src/cmd/cpp/macro.c
index 67af0bd0c..89516a77e 100644
--- a/sys/src/cmd/cpp/macro.c
+++ b/sys/src/cmd/cpp/macro.c
@@ -350,7 +350,7 @@ ispaste(Tokenrow *rtr, Token **ap, Token **an, int *ntok)
 void
 substargs(Nlist *np, Tokenrow *rtr, Tokenrow **atr)
 {
-	Tokenrow ttr;
+	Tokenrow ttr, rp, rn;
 	Token *tp, *ap, *an, *pp, *pn;
 	int ntok, argno, hs;
 
@@ -369,19 +369,25 @@ substargs(Nlist *np, Tokenrow *rtr, Tokenrow **atr)
 			insertrow(rtr, ntok, stringify(atr[argno]));
 		} else if (ispaste(rtr, &ap, &an, &ntok)) { /* first token, just do the next one */
 			pp = ap;
+			memset(&rp, 0, sizeof(rp));
 			pn = an;
+			memset(&rn, 0, sizeof(rp));
 			if (ap && (argno = lookuparg(np, ap)) >= 0){
 				pp = nil;
-				if(atr[argno]->tp != atr[argno]->lp)
-					pp = atr[argno]->lp - 1;
+				rp = *atr[argno];
+				if(rp.tp != rp.lp)
+					pp = --rp.lp;
 			}
 			if (an && (argno = lookuparg(np, an)) >= 0) {
 				pn = nil;
-				if(atr[argno]->tp != atr[argno]->lp)
-					pn = atr[argno]->lp - 1;
+				rn = *atr[argno];
+				if(rn.tp != rn.lp)
+					pn = rn.bp++;
 			}
 			glue(&ttr, pp, pn);
+			insertrow(rtr, 0, &rp);
 			insertrow(rtr, ntok, &ttr);
+			insertrow(rtr, 0, &rn);
 			free(ttr.bp);
 		} else if (rtr->tp->type==NAME) {
 			if((argno = lookuparg(np, rtr->tp)) >= 0) {
diff --git a/sys/src/cmd/cpp/test.c b/sys/src/cmd/cpp/test.c
index 451e364f4..510419050 100644
--- a/sys/src/cmd/cpp/test.c
+++ b/sys/src/cmd/cpp/test.c
@@ -21,6 +21,9 @@ CAT3(blah)
 #define FOO	CAT(BAR, 3)
 FOO
 
+/* Expected: a bc d */
+CAT(a b, c d)
+
 /*
  * CURRENTLY BROKEN:
  *     __VA_ARGS__ requires at least one item.
@@ -58,4 +61,4 @@ g(x+(3,4)-w) | h 5) & m
  *     It should treat no args as a single empty arg list.
 p() i[q()] = { q(1), r(2,3), r(4,), r(,5), r(,) };
 char c[2][6] = { str(hello), str() };
-*/
\ No newline at end of file
+*/