The correctness DynamicTests only ran binary + - * / on a dynamic operand, so
no test recompiled and executed decompiled output for any unary operator. That
gap is why ~ on a dynamic value (issue #3820) shipped uncompilable output
undetected: a correctness case round-trips the decompilation through the
compiler, so it fails the moment the decompiler emits something that does not
recompile.
Add ~, -, +, and ! cases. They pin the runtime semantics of the dynamic unary
path and would have caught the OnesComplement regression directly.
Assisted-by: Claude:claude-opus-4-8:Claude Code
NullPropagationTransform rewrote `c != null ? c.AccessChain : default` to
`c?.AccessChain ?? default` whenever the access-chain result was a non-nullable
value type. For a by-ref-like type (a ref struct such as Span<T>) that form does
not compile: a ref struct cannot be wrapped in Nullable<T> (CS8978). Exclude
by-ref-like return types from the null-coalescing rewrite.
Assisted-by: Copilot:claude-opus-4.8:GitHub Copilot CLI
Compilation uses the .NET builds of the Roslyn toolsets (tasks/netcore*,
bincore csc.dll/vbc.dll launched through the dotnet host). ilasm/ildasm
options use the '-' prefix, which all platforms accept. The dotnet-hosted
compilers have no implicit references or SDK path: net40 compiles pass
mscorlib explicitly, and vbc gets -sdkpath, _MYTYPE=Empty and
-vbruntime:Microsoft.VisualBasic.Core.dll (the facade in the ref packs is
not followed for runtime helpers). The TestRunner gets a self-contained
build for the host platform.
Configurations depending on Windows-only tools or runtimes (legacy
csc/vbc, Roslyn 1.x/2.x, mcs, Force32Bit, executing net40 binaries) are
filtered from the matrix off-Windows via Tester.SupportedOnCurrentPlatform
or gated with [Platform("Win")]. PdbGen comparisons normalize document
name separators, and Correctness/Async uses Console.IsInputRedirected
instead of the Windows-only Console.CapsLock.
Assisted-by: Claude:claude-fable-5:Claude Code
This makes our logic more similar to that used by the dotnet runtime. This lets us infer correct stack types in edge cases such as #2401. It also improves support for obfuscated control flow such as #2878.
The C# translation of StObj will always apply delayed exceptions in these two cases, so putting an instruction with delayed exceptions in that slot would change program semantics.