Auto merge of rust-lang#110801 - WaffleLapkin:io-tests, r=jyn514

Fix `ui/io-checks/inaccessbile-temp-dir.rs` test

Fixes rust-lang#110794

r? `@jyn514`

Author: bors

tests/run-make/inaccessible-temp-dir/Makefile

@@ -0,0 +1,32 @@
+# only-linux
+# ignore-arm - linker error on `armhf-gnu`
+
+include ../tools.mk
+
+# Issue #66530: We would ICE if someone compiled with `-o /dev/null`,
+# because we would try to generate auxiliary files in `/dev/` (which
+# at least the OS X file system rejects).
+#
+# An attempt to `-Ztemps-dir` into a directory we cannot write into should
+# indeed be an error; but not an ICE.
+#
+# However, some folks run tests as root, which can write `/dev/` and end
+# up clobbering `/dev/null`. Instead we'll use an inaccessible path, which
+# also used to ICE, but even root can't magically write there.
+#
+# Note that `-Ztemps-dir` uses `create_dir_all` so it is not sufficient to
+# use a directory with non-existing parent like `/does-not-exist/output`.
+
+all:
+	# Create an inaccessible directory
+	mkdir $(TMPDIR)/inaccessible
+	chmod 000 $(TMPDIR)/inaccessible
+
+	# Run rustc with `-Ztemps-dir` set to a directory 
+	# *inside* the inaccessible one, so that it can't create it
+	$(RUSTC) program.rs -Ztemps-dir=$(TMPDIR)/inaccessible/tmp 2>&1 \
+		| $(CGREP) "failed to find or create the directory specified by `--temps-dir`"
+
+	# Make the inaccessible directory accessible,
+	# so that compiletest can delete the temp dir
+	chmod +rw $(TMPDIR)/inaccessible

tests/run-make/inaccessible-temp-dir/program.rs

@@ -0,0 +1 @@
+fn main() {}

tests/ui/io-checks/inaccessbile-temp-dir.rs

@@ -9,7 +9,7 @@
 // up clobbering `/dev/null`. Instead we'll use a non-existent path, which
 // also used to ICE, but even root can't magically write there.
 
-// compile-flags: -o /does-not-exist/output
+// compile-flags: -o ./does-not-exist/output
 
 // The error-pattern check occurs *before* normalization, and the error patterns
 // are wildly different between build environments. So this is a cop-out (and we
@@ -19,22 +19,14 @@
 // error-pattern: error
 
 // On Mac OS X, we get an error like the below
-// normalize-stderr-test "failed to write bytecode to /does-not-exist/output.non_ice_error_on_worker_io_fail.*" -> "io error modifying /does-not-exist/"
+// normalize-stderr-test "failed to write bytecode to ./does-not-exist/output.non_ice_error_on_worker_io_fail.*" -> "io error modifying ./does-not-exist/"
 
 // On Linux, we get an error like the below
-// normalize-stderr-test "couldn't create a temp dir.*" -> "io error modifying /does-not-exist/"
+// normalize-stderr-test "couldn't create a temp dir.*" -> "io error modifying ./does-not-exist/"
 
 // ignore-windows - this is a unix-specific test
 // ignore-emscripten - the file-system issues do not replicate here
 // ignore-wasm - the file-system issues do not replicate here
 // ignore-arm - the file-system issues do not replicate here, at least on armhf-gnu
 
-#![crate_type="lib"]
-
-#![cfg_attr(not(feature = "std"), no_std)]
-pub mod task {
-    pub mod __internal {
-        use crate::task::Waker;
-    }
-    pub use core::task::Waker;
-}
+#![crate_type = "lib"]

tests/ui/io-checks/inaccessbile-temp-dir.stderr

@@ -1,6 +1,6 @@
 warning: ignoring --out-dir flag due to -o flag
 
-error: io error modifying /does-not-exist/
+error: io error modifying ./does-not-exist/
 
 error: aborting due to previous error; 1 warning emitted