https://issues.dlang.org/show_bug.cgi?id=24706

          Issue ID: 24706
           Summary: Missing errors for first operand of comma expression
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Linux
            Status: NEW
          Severity: minor
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: nick@geany.org

import core.attribute;

@mustuse struct S {}

S fun();

void test()
{
    int x;
    fun(); // ignored value of @mustuse type S
    fun(), x++; // no error

    x++, x; // `x` has no effect
    x, x++; // no error
}

PR incoming.

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