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From: adr <adr@SDF.ORG>
To: 9fans <9fans@9fans.net>
Subject: Re: [9fans] Conversion of constants in C compiler
Date: Thu, 21 Apr 2022 07:54:56 +0000 (UTC)	[thread overview]
Message-ID: <8530f0d7-7c38-92af-d649-23f99645b748@SDF.ORG> (raw)
In-Reply-To: <B84B8B8832E3883C4DB26DBBF3289C95@eigenstate.org>

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On Wed, 20 Apr 2022, ori@eigenstate.org wrote:
> When you have a patch, let me know -- I'll happily test
> and apply to 9front.

Hi ori, this patch applyes to the sources served at 9front.org.
By the way, do you plan to keep in sync
http://only9fans.com/ori/git9/HEAD/info.html or should I forget
about that repo?

Regards,
adr.

--- /n/9front/sys/src/cmd/cc/lex.c      Wed Apr  6 14:45:26 2022
+++ /tmp/lex.c  Thu Apr 21 08:39:14 2022
@@ -848,16 +848,9 @@
                yyerror("overflow in constant");

        vv = yylval.vval;
-       /*
-        * c99 is silly: decimal constants stay signed,
-        * hex and octal go unsigned before widening.
-        */
-       w = 32;
-       if((c1 & (Numdec|Numuns)) == Numdec)
-               w = 31;
-       if(c1 & Numvlong || (c1 & Numlong) == 0 && (uvlong)vv >= 1ULL<<w){
-               if((c1&(Numdec|Numvlong)) == Numdec && vv < 1ULL<<32)
-                       warn(Z, "int constant widened to vlong: %s", symb);
+       if(c1 & Numvlong ||
+         convvtox(vv, TUVLONG) > convvtox(vv, TULONG) ||
+         (c1 & (Numdec|Numuns)) == Numdec && convvtox(vv, TLONG) < 0) {
                if((c1 & Numuns) || convvtox(vv, TVLONG) < 0) {
                        c = LUVLCONST;
                        t = TUVLONG;
@@ -867,7 +860,9 @@
                t = TVLONG;
                goto nret;
        }
-       if(c1 & Numlong) {
+       if(c1 & Numlong ||
+         convvtox(vv, TULONG) > convvtox(vv, TUINT) ||
+         (c1 & (Numdec|Numuns)) == Numdec && convvtox(vv, TINT) < 0) {
                if((c1 & Numuns) || convvtox(vv, TLONG) < 0) {
                        c = LULCONST;
                        t = TULONG;
------------------------------------------
9fans: 9fans
Permalink: https://9fans.topicbox.com/groups/9fans/T22754f10b241991c-Mefe97ddcd27aad8f1a072269
Delivery options: https://9fans.topicbox.com/groups/9fans/subscription

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--- /n/9front/sys/src/cmd/cc/lex.c	Wed Apr  6 14:45:26 2022
+++ /tmp/lex.c	Thu Apr 21 08:39:14 2022
@@ -848,16 +848,9 @@
 		yyerror("overflow in constant");
 
 	vv = yylval.vval;
-	/*
-	 * c99 is silly: decimal constants stay signed,
-	 * hex and octal go unsigned before widening.
-	 */
-	w = 32;
-	if((c1 & (Numdec|Numuns)) == Numdec)
-		w = 31;
-	if(c1 & Numvlong || (c1 & Numlong) == 0 && (uvlong)vv >= 1ULL<<w){
-		if((c1&(Numdec|Numvlong)) == Numdec && vv < 1ULL<<32)
-			warn(Z, "int constant widened to vlong: %s", symb);
+	if(c1 & Numvlong ||
+	  convvtox(vv, TUVLONG) > convvtox(vv, TULONG) ||
+	  (c1 & (Numdec|Numuns)) == Numdec && convvtox(vv, TLONG) < 0) {
 		if((c1 & Numuns) || convvtox(vv, TVLONG) < 0) {
 			c = LUVLCONST;
 			t = TUVLONG;
@@ -867,7 +860,9 @@
 		t = TVLONG;
 		goto nret;
 	}
-	if(c1 & Numlong) {
+	if(c1 & Numlong ||
+	  convvtox(vv, TULONG) > convvtox(vv, TUINT) ||
+	  (c1 & (Numdec|Numuns)) == Numdec && convvtox(vv, TINT) < 0) {
 		if((c1 & Numuns) || convvtox(vv, TLONG) < 0) {
 			c = LULCONST;
 			t = TULONG;

  reply	other threads:[~2022-04-21  7:55 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-04-20 10:19 adr
2022-04-20 11:38 ` Charles Forsyth
2022-04-20 14:37   ` adr
2022-04-20 14:37 ` ori
2022-04-21  7:54   ` adr [this message]
2022-04-21 15:29     ` ori
2022-04-28  1:10     ` ori
2022-05-01 12:03       ` adr
2022-04-28  2:43     ` ori
2022-04-28  3:12       ` ori
2022-05-01 12:35       ` adr
2022-05-09 19:31         ` adr
2022-05-10 13:06           ` adr
2022-05-10 14:48             ` adr
2022-06-06  0:35 adr

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