compiletest: only use make_exe_name for tests that end up being executed.

src/test/ui/consts/const-eval/unused-broken-const.stderr

@@ -1,5 +1,3 @@
-warning: due to multiple output types requested, the explicitly specified output file name will be adapted for each output type
-
 error: any use of this value will cause an error
   --> $DIR/unused-broken-const.rs:5:18
    |

src/test/ui/emit-directives.rs

@@ -1,11 +1,5 @@
-// ignore-tidy-linelength
 // compile-flags:--emit=metadata --error-format=json -Z emit-directives
 // compile-pass
-//
-// Normalization is required to eliminated minor path and filename differences
-// across platforms.
-// normalize-stderr-test: "metadata file written: .*/emit-directives" -> "metadata file written: .../emit-directives"
-// normalize-stderr-test: "emit-directives(\.\w*)?/a(\.\w*)?" -> "emit-directives/a"
 
 // A very basic test for the emission of build directives in JSON output.
 

src/test/ui/emit-directives.stderr

@@ -1 +1 @@
-{"directive":"metadata file written: .../emit-directives/a"}
+{"directive":"metadata file written: $TEST_BUILD_DIR/emit-directives/libemit_directives.rmeta"}

src/test/ui/traits/trait-object-with-self-in-projection-output-repeated-supertrait.rs

@@ -1,5 +1,8 @@
 // compile-pass
 
+// FIXME(eddyb) shorten the name so windows doesn't choke on it.
+#![crate_name = "trait_test"]
+
 // Regression test related to #56288. Check that a supertrait projection (of
 // `Output`) that references `Self` is ok if there is another occurence of
 // the same supertrait that specifies the projection explicitly, even if