v2.020 & v2.021.
//--
import std.stdio;

void main()
{
    writefln(foo(10));
}

int foo(int i)
{
    return i * i;
}
//--
C:\Zz\Downloads>dmd -O -release -inline t.d
C:\dmd\bin\..\src\druntime\import\core\exception.di(12): constructor object.Error.this (invariant(char)[] msg) does not
match parameter types (invariant(char[15u]),invariant(char)[],uint)
C:\dmd\bin\..\src\druntime\import\core\exception.di(12): Error: expected 2 arguments, not 3
C:\dmd\bin\..\src\druntime\import\core\exception.di(12): Error: cannot implicitly convert expression (file) of type inva
riant(char)[] to object.Error
C:\dmd\bin\..\src\druntime\import\core\exception.di(19): constructor object.Error.this (invariant(char)[] msg) does not
match parameter types (invariant(char[17u]),invariant(char)[],uint)
C:\dmd\bin\..\src\druntime\import\core\exception.di(19): Error: expected 2 arguments, not 3
C:\dmd\bin\..\src\druntime\import\core\exception.di(19): Error: cannot implicitly convert expression (file) of type inva
riant(char)[] to object.Error
C:\dmd\bin\..\src\druntime\import\core\exception.di(23): constructor object.Error.this (invariant(char)[] msg) does not
match parameter types (invariant(char)[],invariant(char)[],uint)
C:\dmd\bin\..\src\druntime\import\core\exception.di(23): Error: expected 2 arguments, not 3
C:\dmd\bin\..\src\druntime\import\core\exception.di(23): Error: cannot implicitly convert expression (file) of type inva
riant(char)[] to object.Error
C:\dmd\bin\..\src\druntime\import\core\exception.di(31): constructor object.Error.this (invariant(char)[] msg) does not
match parameter types (invariant(char[18u]),Exception)
C:\dmd\bin\..\src\druntime\import\core\exception.di(31): Error: cannot implicitly convert expression (e) of type object.
Exception to object.Error
C:\dmd\bin\..\src\druntime\import\core\exception.di(53): constructor object.Error.this (invariant(char)[] msg) does not
match parameter types (invariant(char[24u]),invariant(char)[],uint)
C:\dmd\bin\..\src\druntime\import\core\exception.di(53): Error: expected 2 arguments, not 3
C:\dmd\bin\..\src\druntime\import\core\exception.di(53): Error: cannot implicitly convert expression (file) of type inva
riant(char)[] to object.Error
C:\dmd\bin\..\src\druntime\import\core\exception.di(67): constructor object.Error.this (invariant(char)[] msg) does not
match parameter types (invariant(char[34u]),invariant(char)[],uint)
C:\dmd\bin\..\src\druntime\import\core\exception.di(67): Error: expected 2 arguments, not 3
C:\dmd\bin\..\src\druntime\import\core\exception.di(67): Error: cannot implicitly convert expression (file) of type inva
riant(char)[] to object.Error