Consider this:

package test70

import groovy.transform.CompileStatic

@CompileStatic
class Test70 {

	void foo() {
		Object v1 = 'a'
		Object v2 = 'b'
		[v1, v2].each {
			v ->
			if(v instanceof Map) {
				v.entrySet().each { e ->
					def s = e.value
					if(s instanceof String)
					e.value = s.toUpperCase()
				}
			}
		}
	}
}

An error is given on both occurrences of e.value, because e is evaluated as Object instead of Map.Entry.
This used to work until some version of the Greclipse plugin (now I'm on 4.3.0.v202107132103-e2009).
If I compile this with Gradle/Groovy, the JAR is built successfully.

If I remove @CompileStatic, I get underlining for v.entrySet() and again on both occurrences of e.value.

If I try to give e a type in the closure:

				v.entrySet().each { Entry e ->
					def s = e.value
					if(s instanceof String)
					e.value = s.toUpperCase()
				}

I see this:

• with @CompileStatic an additional error is given on Entry, saying it's expecting Object.
• without @CompileStatic, instead, the underlining for e.value is fixed, so the situation improves.