gc: make constant arith errors a little more friendly

Fixes #2804.

R=ken2
CC=golang-dev
https://golang.org/cl/5652067

diff --git a/src/cmd/gc/const.c b/src/cmd/gc/const.c
index 01c4f15b3f376b9935c122463dce3867a1b40623..550e7e494368c324e4d5c671d292e69c53bfa4f6 100644 (file)
--- a/src/cmd/gc/const.c
+++ b/src/cmd/gc/const.c
@@ -589,7 +589,7 @@ evconst(Node *n)
 
        case TUP(OADD, CTINT):
        case TUP(OADD, CTRUNE):
-               mpaddfixfix(v.u.xval, rv.u.xval);
+               mpaddfixfix(v.u.xval, rv.u.xval, 0);
                break;
        case TUP(OSUB, CTINT):
        case TUP(OSUB, CTRUNE):

diff --git a/src/cmd/gc/go.h b/src/cmd/gc/go.h
index 0fde5065772812cbaea55ea1726b6559a88c24f1..cd23b2f08663782f9397c19d0d830abf9b77af7b 100644 (file)
--- a/src/cmd/gc/go.h
+++ b/src/cmd/gc/go.h
@@ -1049,7 +1049,7 @@ void      mpsubfltflt(Mpflt *a, Mpflt *b);
 /*
  *     mparith2.c
  */
-void   mpaddfixfix(Mpint *a, Mpint *b);
+void   mpaddfixfix(Mpint *a, Mpint *b, int);
 void   mpandfixfix(Mpint *a, Mpint *b);
 void   mpandnotfixfix(Mpint *a, Mpint *b);
 void   mpdivfract(Mpint *a, Mpint *b);

diff --git a/src/cmd/gc/go.y b/src/cmd/gc/go.y
index ccbb90f47b20863ceda9a7b343149bd3301f1a7d..ffd9b73737fd62a2e94614242704d09f0a7888ae 100644 (file)
--- a/src/cmd/gc/go.y
+++ b/src/cmd/gc/go.y
@@ -2027,7 +2027,7 @@ hidden_constant:
        {
                if($2->val.ctype == CTRUNE && $4->val.ctype == CTINT) {
                        $$ = $2;
-                       mpaddfixfix($2->val.u.xval, $4->val.u.xval);
+                       mpaddfixfix($2->val.u.xval, $4->val.u.xval, 0);
                        break;
                }
                $$ = nodcplxlit($2->val, $4->val);

diff --git a/src/cmd/gc/mparith1.c b/src/cmd/gc/mparith1.c
index 2b7307e1a41623127229d8a91b36a59b14736b8e..33fa90e2e0a38372a352edaa57e0b289b59694d3 100644 (file)
--- a/src/cmd/gc/mparith1.c
+++ b/src/cmd/gc/mparith1.c
@@ -72,7 +72,7 @@ void
 mpsubfixfix(Mpint *a, Mpint *b)
 {
        mpnegfix(a);
-       mpaddfixfix(a, b);
+       mpaddfixfix(a, b, 0);
        mpnegfix(a);
 }
 
@@ -90,7 +90,7 @@ mpaddcfix(Mpint *a, vlong c)
        Mpint b;
 
        mpmovecfix(&b, c);
-       mpaddfixfix(a, &b);
+       mpaddfixfix(a, &b, 0);
 }
 
 void
@@ -302,7 +302,7 @@ mpatoflt(Mpflt *a, char *as)
                                if(c >= '0' && c <= '9') {
                                        ex = ex*10 + (c-'0');
                                        if(ex > 1e8) {
-                                               yyerror("exponent out of range");
+                                               yyerror("constant exponent out of range: %s", as);
                                                errorexit();
                                        }
                                        continue;
@@ -343,7 +343,7 @@ out:
        return;
 
 bad:
-       yyerror("set ovf in mpatof");
+       yyerror("constant too large: %s", as);
        mpmovecflt(a, 0.0);
 }
 
@@ -431,7 +431,7 @@ out:
        return;
 
 bad:
-       yyerror("set ovf in mpatov: %s", as);
+       yyerror("constant too large: %s", as);
        mpmovecfix(a, 0);
 }
 

diff --git a/src/cmd/gc/mparith2.c b/src/cmd/gc/mparith2.c
index 71cc29c99a1c256789ef06d4a3fdf188bd21a89e..c802e4468a836f69a3c2ebb56fc7adbef7502e30 100644 (file)
--- a/src/cmd/gc/mparith2.c
+++ b/src/cmd/gc/mparith2.c
@@ -121,7 +121,8 @@ mpcmp(Mpint *a, Mpint *b)
        int i;
 
        if(a->ovf || b->ovf) {
-               yyerror("ovf in cmp");
+               if(nsavederrors+nerrors == 0)
+                       yyerror("ovf in cmp");
                return 0;
        }
 
@@ -190,13 +191,14 @@ mpshiftfix(Mpint *a, int s)
 /// implements fix arihmetic
 
 void
-mpaddfixfix(Mpint *a, Mpint *b)
+mpaddfixfix(Mpint *a, Mpint *b, int quiet)
 {
        int i, c;
        long x, *a1, *b1;
 
        if(a->ovf || b->ovf) {
-               yyerror("ovf in mpaddxx");
+               if(nsavederrors+nerrors == 0)
+                       yyerror("ovf in mpaddxx");
                a->ovf = 1;
                return;
        }
@@ -218,8 +220,8 @@ mpaddfixfix(Mpint *a, Mpint *b)
                *a1++ = x;
        }
        a->ovf = c;
-       if(a->ovf)
-               yyerror("set ovf in mpaddxx");
+       if(a->ovf && !quiet)
+               yyerror("constant addition overflow");
 
        return;
 
@@ -266,7 +268,8 @@ mpmulfixfix(Mpint *a, Mpint *b)
        Mpint s, q;
 
        if(a->ovf || b->ovf) {
-               yyerror("ovf in mpmulfixfix");
+               if(nsavederrors+nerrors == 0)
+                       yyerror("ovf in mpmulfixfix");
                a->ovf = 1;
                return;
        }
@@ -290,7 +293,7 @@ mpmulfixfix(Mpint *a, Mpint *b)
                x = *a1++;
                for(j=0; j<Mpscale; j++) {
                        if(x & 1)
-                               mpaddfixfix(&q, &s);
+                               mpaddfixfix(&q, &s, 1);
                        mplsh(&s);
                        x >>= 1;
                }
@@ -299,7 +302,7 @@ mpmulfixfix(Mpint *a, Mpint *b)
        q.neg = a->neg ^ b->neg;
        mpmovefixfix(a, &q);
        if(a->ovf)
-               yyerror("set ovf in mpmulfixfix");
+               yyerror("constant multiplication overflow");
 }
 
 void
@@ -311,7 +314,8 @@ mpmulfract(Mpint *a, Mpint *b)
        Mpint s, q;
 
        if(a->ovf || b->ovf) {
-               yyerror("ovf in mpmulflt");
+               if(nsavederrors+nerrors == 0)
+                       yyerror("ovf in mpmulflt");
                a->ovf = 1;
                return;
        }
@@ -334,7 +338,7 @@ mpmulfract(Mpint *a, Mpint *b)
                for(j=0; j<Mpscale; j++) {
                        x <<= 1;
                        if(x & Mpbase)
-                               mpaddfixfix(&q, &s);
+                               mpaddfixfix(&q, &s, 1);
                        mprsh(&s);
                }
        }
@@ -342,7 +346,7 @@ mpmulfract(Mpint *a, Mpint *b)
        q.neg = a->neg ^ b->neg;
        mpmovefixfix(a, &q);
        if(a->ovf)
-               yyerror("set ovf in mpmulflt");
+               yyerror("constant multiplication overflow");
 }
 
 void
@@ -353,7 +357,8 @@ mporfixfix(Mpint *a, Mpint *b)
 
        x = 0;
        if(a->ovf || b->ovf) {
-               yyerror("ovf in mporfixfix");
+               if(nsavederrors+nerrors == 0)
+                       yyerror("ovf in mporfixfix");
                mpmovecfix(a, 0);
                a->ovf = 1;
                return;
@@ -388,7 +393,8 @@ mpandfixfix(Mpint *a, Mpint *b)
 
        x = 0;
        if(a->ovf || b->ovf) {
-               yyerror("ovf in mpandfixfix");
+               if(nsavederrors+nerrors == 0)
+                       yyerror("ovf in mpandfixfix");
                mpmovecfix(a, 0);
                a->ovf = 1;
                return;
@@ -423,7 +429,8 @@ mpandnotfixfix(Mpint *a, Mpint *b)
 
        x = 0;
        if(a->ovf || b->ovf) {
-               yyerror("ovf in mpandnotfixfix");
+               if(nsavederrors+nerrors == 0)
+                       yyerror("ovf in mpandnotfixfix");
                mpmovecfix(a, 0);
                a->ovf = 1;
                return;
@@ -458,7 +465,8 @@ mpxorfixfix(Mpint *a, Mpint *b)
 
        x = 0;
        if(a->ovf || b->ovf) {
-               yyerror("ovf in mporfixfix");
+               if(nsavederrors+nerrors == 0)
+                       yyerror("ovf in mporfixfix");
                mpmovecfix(a, 0);
                a->ovf = 1;
                return;
@@ -491,7 +499,8 @@ mplshfixfix(Mpint *a, Mpint *b)
        vlong s;
 
        if(a->ovf || b->ovf) {
-               yyerror("ovf in mporfixfix");
+               if(nsavederrors+nerrors == 0)
+                       yyerror("ovf in mporfixfix");
                mpmovecfix(a, 0);
                a->ovf = 1;
                return;
@@ -512,7 +521,8 @@ mprshfixfix(Mpint *a, Mpint *b)
        vlong s;
 
        if(a->ovf || b->ovf) {
-               yyerror("ovf in mprshfixfix");
+               if(nsavederrors+nerrors == 0)
+                       yyerror("ovf in mprshfixfix");
                mpmovecfix(a, 0);
                a->ovf = 1;
                return;
@@ -542,7 +552,8 @@ mpgetfix(Mpint *a)
        vlong v;
 
        if(a->ovf) {
-               yyerror("constant overflow");
+               if(nsavederrors+nerrors == 0)
+                       yyerror("constant overflow");
                return 0;
        }
 
@@ -605,7 +616,7 @@ mpdivmodfixfix(Mpint *q, Mpint *r, Mpint *n, Mpint *d)
                r->ovf = 1;
                n->neg = ns;
                d->neg = ds;
-               yyerror("set ovf in mpdivmodfixfix");
+               yyerror("constant division overflow");
                return;
        }
 

diff --git a/src/cmd/gc/mparith3.c b/src/cmd/gc/mparith3.c
index 0c6c5a03b9de2d73342e4dd9016f794ece69a3a0..f8344c9b4e51c51311714cc93bf7b95225437062 100644 (file)
--- a/src/cmd/gc/mparith3.c
+++ b/src/cmd/gc/mparith3.c
@@ -89,17 +89,17 @@ mpaddfltflt(Mpflt *a, Mpflt *b)
                // a is larger, shift b right
                mpmovefltflt(&c, b);
                mpshiftfix(&c.val, -s);
-               mpaddfixfix(&a->val, &c.val);
+               mpaddfixfix(&a->val, &c.val, 0);
                goto out;
        }
        if(s < 0) {
                // b is larger, shift a right
                mpshiftfix(&a->val, s);
                a->exp -= s;
-               mpaddfixfix(&a->val, &b->val);
+               mpaddfixfix(&a->val, &b->val, 0);
                goto out;
        }
-       mpaddfixfix(&a->val, &b->val);
+       mpaddfixfix(&a->val, &b->val, 0);
 
 out:
        mpnorm(a);
@@ -153,7 +153,7 @@ mpdivfltflt(Mpflt *a, Mpflt *b)
                a->exp = 0;
                a->val.neg = 0;
                a->val.ovf = 1;
-               yyerror("mpdivfltflt divide by zero");
+               yyerror("constant division by zero");
                return;
        }
 
@@ -185,7 +185,7 @@ mpgetflt(Mpflt *a)
        uvlong v, vm;
        double f;
 
-       if(a->val.ovf)
+       if(a->val.ovf && nsavederrors+nerrors == 0)
                yyerror("mpgetflt ovf");
 
        s = sigfig(a);

diff --git a/src/cmd/gc/y.tab.c b/src/cmd/gc/y.tab.c
index d2aaa050461ab32634ebddbc315ecb980c6d73ec..2772575087843b23f2bf750b332790e88bd63977 100644 (file)
--- a/src/cmd/gc/y.tab.c
+++ b/src/cmd/gc/y.tab.c
@@ -5188,7 +5188,7 @@ yyreduce:
     {
                if((yyvsp[(2) - (5)].node)->val.ctype == CTRUNE && (yyvsp[(4) - (5)].node)->val.ctype == CTINT) {
                        (yyval.node) = (yyvsp[(2) - (5)].node);
-                       mpaddfixfix((yyvsp[(2) - (5)].node)->val.u.xval, (yyvsp[(4) - (5)].node)->val.u.xval);
+                       mpaddfixfix((yyvsp[(2) - (5)].node)->val.u.xval, (yyvsp[(4) - (5)].node)->val.u.xval, 0);
                        break;
                }
                (yyval.node) = nodcplxlit((yyvsp[(2) - (5)].node)->val, (yyvsp[(4) - (5)].node)->val);

diff --git a/src/cmd/go/build.go b/src/cmd/go/build.go
index 0956a35eae9183a890cfcc73a9556066c034caeb..da046eedbc26c989f67e9a8bf5998c9330413d46 100644 (file)
--- a/src/cmd/go/build.go
+++ b/src/cmd/go/build.go
@@ -671,6 +671,13 @@ func (b *builder) install(a *action) error {
                }
        }
 
+       // remove object dir to keep the amount of
+       // garbage down in a large build.  On an operating system
+       // with aggressive buffering, cleaning incrementally like
+       // this keeps the intermediate objects from hitting the disk.
+       defer os.RemoveAll(a1.objdir)
+       defer os.Remove(a1.target)
+
        return b.copyFile(a.target, a1.target, perm)
 }
 

diff --git a/test/const2.go b/test/const2.go
index bea1b991254423bb37f171bc7d69de6a5f7d2be2..b0837354abfeeedf30e2724d6472b41eeead01b0 100644 (file)
--- a/test/const2.go
+++ b/test/const2.go
@@ -10,3 +10,7 @@ const (
        A int = 1
        B byte; // ERROR "type without expr|expected .=."
 )
+
+const LargeA = 1000000000000000000
+const LargeB = LargeA * LargeA * LargeA
+const LargeC = LargeB * LargeB * LargeB  // ERROR "constant multiplication overflow"