https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77938
Bug ID: 77938
Summary: missing tailcall optimization in case when local
variable escapes
Product: gcc
Version: 6.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: vanyacpp at gmail dot com
Target Milestone: ---
GCC does not eliminate tailcalls in case when an address of any local variable
escapes the function. Consider the following code:
void escape(int& a);
void callee();
void caller()
{
{
int local;
escape(local);
}
callee();
}
The variable "local" escaped, but it is dead by the time control reaches the
call to callee(). Therefore callee can not access it without invoking undefined
behavior. As the result the call to callee() can be a tailcall.
