stab at fixing clang crash

Author: HenryHRich

jsrc/ar.c

@@ -1214,6 +1214,20 @@ static DF2(jtfold12){F12IP;A z,vz;
         // we are adding uz to a recursible block, with transfer of ownership.  The new owner protects the block.  If uz is abandoned it is safe to zap even if it is x.  Sets new uz
       // Fold Multiple.  Add the new value to the result array
       UI newslot=AN(zz);  // where the new value will go
+#if 1   // test version to try to eliminate crash
+      if(withprob(newslot==zzalloc,0.03)){  // current alloc full?
+       // current alloc is full.  Double the allocation, swap it with zz (transferring ownership), and copy the data
+       zzalloc=2*zzalloc+(AKXR(1)>>LGSZI);  // new allocation, cacheline multiple
+// obsolete        A zznew; GATV0E(zznew,INT,zzalloc,1,goto exitpop;) A *zznewzap=AZAPLOC(zznew); A *zzzap=AZAPLOC(zz);  // allocate, & get pointers to tstack slots old & new
+       A zznew; GATV0E(zznew,INT,zzalloc,1,goto exitpop;) ACINITUNPUSH(zznew)  // allocate & zap new block
+// obsolete  AT(zz)=INT; AFLAG(zz)=0;
+       JMC(AAV1(zznew),AAV1(zz),newslot<<LGSZI,0) AZAPLOC(zznew)=AZAPLOC(zz);
+       AT(zznew)=BOX; AFLAG(zznew)=BOX&RECURSIBLE;    // new zz now has pointers to allocated blocks and to its dedicated zaploc
+       AN(zznew)=newslot+1; AAV(zznew)[newslot]=z;  // AAV not AAV1
+       *AZAPLOC(zz)=zznew; mf(zz); zz=zznew;  // swap buffers, transferring ownership to zznew & protecting it; free zz using mf to avoid traversing boxes
+// obsolete  *zznewzap=zz;
+      }else{AAV1(zz)[newslot]=z; AN(zz)=newslot+1;}  // install the new value & account for it in len
+#else
       if(withprob(newslot==zzalloc,0.03)){  // current alloc full?
        // current alloc is full.  Double the allocation, swap it with zz (transferring ownership), and copy the data
        zzalloc=2*zzalloc+(AKXR(1)>>LGSZI);  // new allocation, cacheline multiple
@@ -1225,6 +1239,7 @@ static DF2(jtfold12){F12IP;A z,vz;
        AT(zz)=BOX; AFLAG(zz)=BOX&RECURSIBLE;    // new zz now has pointers to allocated blocks and to its dedicated zaploc
       }
       AAV1(zz)[newslot]=z; AN(zz)=newslot+1;  // install the new value & account for it in len
+#endif
      }else{
       // Fold Single.  Replace the value in zz
 // obsolete      ra(z)  // uz is not guaranteed to stay in the result till the end; therefore we must not zap it for fold single since it might be w also.