test unstable values of -C link-self-contained

These values require using `-Z unstable options`

Author: lqd

src/test/ui/linkers/unstable_link_self_contained.all.stderr

@@ -0,0 +1,2 @@
+error: only `-C link-self-contained` values `y`/`yes`/`on`/`n`/`no`/`off` are stable, the `-Z unstable-options` flag must also be passed to use the unstable values
+

src/test/ui/linkers/unstable_link_self_contained.auto.stderr

@@ -0,0 +1,2 @@
+error: only `-C link-self-contained` values `y`/`yes`/`on`/`n`/`no`/`off` are stable, the `-Z unstable-options` flag must also be passed to use the unstable values
+

src/test/ui/linkers/unstable_link_self_contained.crt.stderr

@@ -0,0 +1,2 @@
+error: only `-C link-self-contained` values `y`/`yes`/`on`/`n`/`no`/`off` are stable, the `-Z unstable-options` flag must also be passed to use the unstable values
+

src/test/ui/linkers/unstable_link_self_contained.linker.stderr

@@ -0,0 +1,2 @@
+error: only `-C link-self-contained` values `y`/`yes`/`on`/`n`/`no`/`off` are stable, the `-Z unstable-options` flag must also be passed to use the unstable values
+

src/test/ui/linkers/unstable_link_self_contained.rs

@@ -0,0 +1,11 @@
+// check-fail
+// revisions: crt auto linker all
+// [crt] compile-flags: -C link-self-contained=crt
+// [auto] compile-flags: -C link-self-contained=auto
+// [linker] compile-flags: -C link-self-contained=linker
+// [all] compile-flags: -C link-self-contained=all
+
+// Test ensuring that the unstable values of the stable `-C link-self-contained` flag
+// require using `-Z unstable options`
+
+fn main() {}