https://issues.dlang.org/show_bug.cgi?id=14210
Issue ID: 14210
Summary: invalid merging of template instances
Product: D
Version: D2
Hardware: All
OS: All
Status: NEW
Severity: major
Priority: P1
Component: DMD
Assignee: [email protected]
Reporter: [email protected]
compiler erroneously merges templates with different delegate types. let's run
the following code:
=== test.d ===
void test(DT) (string name, DT dg) {
import std.stdio;
writeln(":: ", name);
writeln(typeof(dg).stringof);
}
void main () {
test("001", (int a=40) => a+2);
test("000", (int a) => a+0);
}
===
output:
:: 001
int function(int a = 40) pure nothrow @nogc @safe
:: 000
int function(int a = 40) pure nothrow @nogc @safe
now let's change `main` to:
===
void main () {
test("000", (int a) => a+0);
test("001", (int a=40) => a+2);
}
===
output:
:: 000
int function(int a) pure nothrow @nogc @safe
:: 001
int function(int a) pure nothrow @nogc @safe
both results are obviously wrong, 'cause compiler should not merge two
instantiations. yet compiler checks for merge possibility by checking mangled
names, and both types mangles to the same string.
this breaks automatic CTFE wrapping of functions for some scripting engines,
and possibly many more cases.
--
