Cannot use local variable 'var' before it is declared

[greenozon]

ILSpy version 5.0.0.5057-preview4

ref to method

public void RemoveConsole()

it is having issue wtih local var
It is declared nowhere..

VS error:

error CS0841: Cannot use local variable 'installation' before it is declared

[siegfriedpammer]

I cannot find an undeclared variable in the source code. Could you please post the snippet showing the error? Thank you!

[greenozon]

wrong input, it's here

https://www.sendspace.com/file/0iis4h

please also pay attention that RemoveConsole() method has way too many goto's...

[siegfriedpammer]

In the assembly you provided there is no method called "RemoveConsole". Can you please clarify? Thank you!

[greenozon]

pardon again

code snippet

					if (Program.Storage.DirectoryExists(_customPath))
					{
						Program.Out.WriteLine();
						Program.Out.WriteLine($"Removing from custom path: '{_customPath}'.");
						if (Program.Where.FindGitInstallation(_customPath, KnownDistribution.GitForWindows64v2, out installation) || Program.Where.FindGitInstallation(_customPath, KnownDistribution.GitForWindows32v2, out installation) || Program.Where.FindGitInstallation(_customPath, KnownDistribution.GitForWindows32v1, out Installation installation))
						{
							Program.Trace.WriteLine($"Git found: '{installation.Path}'.", "E:\\A\\_work\\319\\s\\Cli\\Manager\\Installer.cs", 530, "RemoveConsole");
							installations = new List<Installation>
							{
								installation
							};
						}
						goto IL_01f2;
					}

see the "out installation" - it is used without declaration

BTW, ILSpy does not show body of inside types!?

https://www.sendspace.com/file/usqvp1

[siegfriedpammer]

The assembly looks like it only contains internal types. You will have to activate the "Show internal types and members" option. (The toolbar button next to "Reload assemblies").

[siegfriedpammer]

Can you please provide all assemblies that are referenced by this one?

I cannot reproduce this, because the method in question is defined in a referenced assembly.

            if (Program.Where.FindGitInstallation(_customPath, 2, ref val)
                            || Program.Where.FindGitInstallation(_customPath, 1, ref val)
                            || Program.Where.FindGitInstallation(_customPath, 0, ref val))

out parameters cannot be detected, if the definition cannot be found.

From the code you posted:

       if (Program.Where.FindGitInstallation(_customPath, KnownDistribution.GitForWindows64v2, out installation)
                     || Program.Where.FindGitInstallation(_customPath, KnownDistribution.GitForWindows32v2, out installation)
                     || Program.Where.FindGitInstallation(_customPath, KnownDistribution.GitForWindows32v1, out Installation installation))

Seems like the out var declaration is added in the wrong place.

[greenozon]

Thanks for tip about internal types! forget about it at all :)
it worked like a charm

2. here is a full set of ref assemblies
   issue still present if having them all resolved
   similar issue in another method - DeployConsole()

https://www.sendspace.com/file/3xetv8

[siegfriedpammer]

As already mentioned in #1634 the problem is that DeclareVariables visits the nodes of the syntax tree in the order of the linked list used internally. Some AST transforms however, change the order of their children in a way that the order of the nodes in the linked list no longer reflects the order in which they will be written when printed as source code. But DeclareVariables assumes this and due to that the transform ends up declaring the variable in the wrong place.

@dgrunwald I think, DeclareVariables will either have to traverse the nodes the same way CSharpOutputVisitor does (but this is a major rewrite using an explicit visitor pattern, which will make the code bloated) or we fix this in the C# AST. The linked list approach has caused problems in the past (#1202).

[siegfriedpammer]

I have added a simple fix for this particular problem. Note that this is not yet included in the just released preview4. I was too slow :)