decimal has no IL literal: legacy csc compiles 0m to a Decimal.Zero
field load, which already decompiled to the literal, but Roslyn
compiles it to a zero-initialization, which decompiled to
default(decimal). The two forms are bit-identical for decimal, so the
literal is no less faithful to the IL and matches what a human writes;
it also removes the per-compiler split in the CompoundAssignmentTest
fixture.
Assisted-by: Claude:claude-fable-5:Claude Code
Siegfried Pammer