Keep track of stack usage, report line that used the most

This won't keep track of everything, but was useful in tracking down
some recursive variables in the android build that shouldn't have been
recursive (they were using 1MB+ of stack).

Change-Id: I5e6b70480cffbebb09dfd72276017559480da948

1 files changed, 5 insertions, 2 deletions

diff --git a/var.cc b/var.cc
index 27d92c7..14ccee6 100644
--- a/var.cc
+++ b/var.cc
@@ -59,7 +59,8 @@ SimpleVar::SimpleVar(VarOrigin origin) : origin_(origin) {}
 SimpleVar::SimpleVar(const string& v, VarOrigin origin)
     : v_(v), origin_(origin) {}
 
-void SimpleVar::Eval(Evaluator*, string* s) const {
+void SimpleVar::Eval(Evaluator* ev, string* s) const {
+  ev->CheckStack();
   *s += v_;
 }
 
@@ -82,10 +83,12 @@ RecursiveVar::RecursiveVar(Value* v, VarOrigin origin, StringPiece orig)
     : v_(v), origin_(origin), orig_(orig) {}
 
 void RecursiveVar::Eval(Evaluator* ev, string* s) const {
+  ev->CheckStack();
   v_->Eval(ev, s);
 }
 
-void RecursiveVar::AppendVar(Evaluator*, Value* v) {
+void RecursiveVar::AppendVar(Evaluator* ev, Value* v) {
+  ev->CheckStack();
   v_ = NewExpr3(v_, NewLiteral(" "), v);
 }