Briefly glanced over changes (commit 2), not a complete review pass #Closed

@AlekseyTs @dotnet/roslyn-compiler for reviews, thanks

@dotnet/roslyn-compiler for reviews, thanks

It also looks like this decision is a reversal of ref safety changes made in #24904, which were themselves a reversal of a prior state where the ref-safe-context of an assignment was the RHS.

Interesting find, thanks.

Note that there are already some places where RHS is used, it's just not very consistent. For example:

In my view this emphasizes that this area needs to be well-specified. Basically I am OK with letting this PR in as it is now, but, let's make sure that before too long we get the behavior we actually want recorded in the standard. I would be happy to work together on this.

The standard has this section, but it doesn't seem to answer what the safe-context should be for assignment operators I think:

16.4.15.5 Operators

The application of a user-defined operator is treated as a method invocation (§16.4.15.6).

For an operator that yields a value, such as e1 + e2 or c ? e1 : e2, the safe-context of the result is the narrowest context among the safe-contexts of the operands of the operator. As a consequence, for a unary operator that yields a value, such as +e, the safe-context of the result is the safe-context of the operand.

Note: The first operand of a conditional operator is a bool, so its safe-context is caller-context. It follows that the resulting safe-context is the narrowest safe-context of the second and third operand. end note

Filed dotnet/csharpstandard#1444