[noescape-by-default] Expand useful diagnostics to more cases

Extends the more useful diagnostics for non-escaping function
parameters used in @escaping contexts to apply to all functions that
are equivalent modulo ExtInfo.

Author: milseman

lib/Sema/CSDiag.cpp

@@ -3613,8 +3613,8 @@ static bool tryDiagnoseNonEscapingParameterToEscaping(Expr *expr, Type srcType,
   if (!srcFT || !destFT || !srcFT->isNoEscape() || destFT->isNoEscape())
     return false;
 
-  // Function types must be equivalent modulo @escaping
-  if (destFT != srcFT->withExtInfo(srcFT->getExtInfo().withNoEscape(false)))
+  // Function types must be equivalent modulo @escaping, @convention, etc.
+  if (destFT != srcFT->withExtInfo(destFT->getExtInfo()))
     return false;
 
   // Pick a specific diagnostic for the specific use

test/attr/attr_autoclosure.swift

@@ -55,7 +55,9 @@ func overloadedEach<P: P2>(_ source: P, _ closure: @escaping () -> ()) {
 struct S : P2 {
   typealias Element = Int
   func each(_ closure: @autoclosure () -> ()) {
-    overloadedEach(self, closure) // expected-error {{invalid conversion from non-escaping function of type '@autoclosure () -> ()' to potentially escaping function type '() -> ()'}}
+    // expected-note@-1{{parameter 'closure' is implicitly non-escaping because it was declared @autoclosure}}
+
+    overloadedEach(self, closure) // expected-error {{passing non-escaping parameter 'closure' to function expecting an @escaping closure}}
   }
 }
 
@@ -87,7 +89,9 @@ class Sub : Super {
 func func12_sink(_ x: @escaping () -> Int) { }
 
 func func12a(_ x: @autoclosure () -> Int) {
-  func12_sink(x) // expected-error{{invalid conversion from non-escaping function of type '@autoclosure () -> Int' to potentially escaping function type '() -> Int'}}
+    // expected-note@-1{{parameter 'x' is implicitly non-escaping because it was declared @autoclosure}}
+
+  func12_sink(x) // expected-error {{passing non-escaping parameter 'x' to function expecting an @escaping closure}}
 }
 func func12b(_ x: @autoclosure(escaping) () -> Int) {
   func12_sink(x)

test/attr/attr_escaping.swift

@@ -38,3 +38,11 @@ struct StoresClosure {
   }
 }
 
+func takesEscapingBlock(_ fn: @escaping @convention(block) () -> Void) {
+  fn()
+}
+func callEscapingWithNoEscapeBlock(_ fn: () -> Void) {
+  // expected-note@-1{{parameter 'fn' is implicitly non-escaping}} {{42-42=@escaping }}
+
+  takesEscapingBlock(fn) // expected-error{{passing non-escaping parameter 'fn' to function expecting an @escaping closure}}
+}