OPT(AST_Seq, function(self, compressor){
if (!compressor.option("side_effects"))
return self;
- if (!self.car.has_side_effects())
- return self.cdr;
+ if (!self.car.has_side_effects()) {
+ // we shouldn't compress (1,eval)(something) to
+ // eval(something) because that changes the meaning of
+ // eval (becomes lexical instead of global).
+ var p;
+ if (!(self.cdr instanceof AST_SymbolRef
+ && self.cdr.name == "eval"
+ && self.cdr.undeclared()
+ && (p = compressor.parent()) instanceof AST_Call
+ && p.expression === self)) {
+ return self.cdr;
+ }
+ }
if (compressor.option("cascade")) {
if (self.car instanceof AST_Assign
&& !self.car.left.has_side_effects()