[Assert Triggered] MaybeODRUseExprs.empty() && "Leftover expressions for odr-use checking"

Description
I'm hitting an assert with a message "MaybeODRUseExprs.empty() && "Leftover expressions for odr-use checking""

This started happening after I added typedefs for vector and matrix with identical identifiers as HLSL's builtins in my own namespace.

Steps to Reproduce
I've setup a http://godbolt.devsh.eu which builds latest DXC from trunk, because the official Godbolt is like 5 months behind.

Unfortunately I have no clue if this only happens in SPIR-V out or DXIL too because I don't have a debug build of DXC.exe around.
(I'd kill for a -print-asserts option that would print the messages even in Release builds)

Sorry about the long link, we haven't made the short ones work yet (and persist across container updates).
link

Actual Behavior
The shader still compiles, I just hit this nasty assert.

Environment

• DXC version dxcompiler.dll: 1.7 - 1.7.0.4202 (050946367)
• Host Operating System Windows

Start by reproducing the assertion with the linked Godbolt example and a debug DXC build, then trace the "Leftover expressions for odr-use checking" assertion through the compiler's ODR-use checking code. Compare behavior with and without the user-defined vector and matrix typedefs, and add a regression test demonstrating that the shader compiles without triggering the assertion.