From 2a89b74bc75d1b30f5e71091cc66fc9f5789d69a Mon Sep 17 00:00:00 2001
From: Ralf Jung <post@ralfj.de>
Date: Sat, 25 Nov 2023 10:11:05 +0100
Subject: [PATCH 1/2] run the provenance-gc=1 test on all targets, but only for
 some of the tests

before: only on Linux host, all tests
after: only the test suite itself (not cargo-miri or the mir-opt-level=4 run),
on all hosts for the host target and on Linux for all "full" targets.
---
 src/tools/miri/.github/workflows/ci.yml |  4 ----
 src/tools/miri/ci.sh                    | 17 ++++++++++++-----
 2 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/src/tools/miri/.github/workflows/ci.yml b/src/tools/miri/.github/workflows/ci.yml
index 554a12909fc..dec85e9232f 100644
--- a/src/tools/miri/.github/workflows/ci.yml
+++ b/src/tools/miri/.github/workflows/ci.yml
@@ -35,10 +35,6 @@ jobs:
     steps:
       - uses: actions/checkout@v3
 
-      - name: Set the tag GC interval to 1 on linux
-        if: runner.os == 'Linux'
-        run: echo "MIRIFLAGS=-Zmiri-provenance-gc=1" >> $GITHUB_ENV
-
       # Cache the global cargo directory, but NOT the local `target` directory which
       # we cannot reuse anyway when the nightly changes (and it grows quite large
       # over time).
diff --git a/src/tools/miri/ci.sh b/src/tools/miri/ci.sh
index 378d7744cf2..0492953671e 100755
--- a/src/tools/miri/ci.sh
+++ b/src/tools/miri/ci.sh
@@ -30,16 +30,23 @@ endgroup
 
 # Test
 function run_tests {
-  if [ -n "${MIRI_TEST_TARGET+exists}" ]; then
+  if [ -n "${MIRI_TEST_TARGET:-}" ]; then
     begingroup "Testing foreign architecture $MIRI_TEST_TARGET"
   else
     begingroup "Testing host architecture"
   fi
 
   ## ui test suite
-  ./miri test
-  if [ -z "${MIRI_TEST_TARGET+exists}" ]; then
-    # Host-only tests: running these on all targets is unlikely to catch more problems and would
+  # On the host and on Linux, also stress-test the GC.
+  if [ -z "${MIRI_TEST_TARGET:-}" ] || [ "$HOST_TARGET" = x86_64-unknown-linux-gnu ]; then
+    MIRIFLAGS="${MIRIFLAGS:-} -Zmiri-provenance-gc=1" ./miri test
+  else
+    ./miri test
+  fi
+
+  # Host-only tests
+  if [ -z "${MIRI_TEST_TARGET:-}" ]; then
+    # Running these on all targets is unlikely to catch more problems and would
     # cost a lot of CI time.
 
     # Tests with optimizations (`-O` is what cargo passes, but crank MIR optimizations up all the
@@ -85,7 +92,7 @@ function run_tests {
 }
 
 function run_tests_minimal {
-  if [ -n "${MIRI_TEST_TARGET+exists}" ]; then
+  if [ -n "${MIRI_TEST_TARGET:-}" ]; then
     begingroup "Testing MINIMAL foreign architecture $MIRI_TEST_TARGET: only testing $@"
   else
     begingroup "Testing MINIMAL host architecture: only testing $@"

From 695f1a515e532e079545982b63906233879959f4 Mon Sep 17 00:00:00 2001
From: Ralf Jung <post@ralfj.de>
Date: Sat, 25 Nov 2023 13:09:35 +0100
Subject: [PATCH 2/2] tweak ci.sh

---
 src/tools/miri/ci.sh | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/tools/miri/ci.sh b/src/tools/miri/ci.sh
index 0492953671e..34892489c80 100755
--- a/src/tools/miri/ci.sh
+++ b/src/tools/miri/ci.sh
@@ -95,7 +95,8 @@ function run_tests_minimal {
   if [ -n "${MIRI_TEST_TARGET:-}" ]; then
     begingroup "Testing MINIMAL foreign architecture $MIRI_TEST_TARGET: only testing $@"
   else
-    begingroup "Testing MINIMAL host architecture: only testing $@"
+    echo "run_tests_minimal requires MIRI_TEST_TARGET to be set"
+    exit 1
   fi
 
   ./miri test -- "$@"
@@ -106,15 +107,20 @@ function run_tests_minimal {
   endgroup
 }
 
-# host
+## Main Testing Logic ##
+
+# Host target.
 run_tests
 
+# Extra targets.
+# In particular, fully cover all tier 1 targets.
 case $HOST_TARGET in
   x86_64-unknown-linux-gnu)
     MIRI_TEST_TARGET=i686-unknown-linux-gnu run_tests
     MIRI_TEST_TARGET=aarch64-unknown-linux-gnu run_tests
     MIRI_TEST_TARGET=aarch64-apple-darwin run_tests
     MIRI_TEST_TARGET=i686-pc-windows-gnu run_tests
+    # Some targets are only partially supported.
     MIRI_TEST_TARGET=x86_64-unknown-freebsd run_tests_minimal hello integer vec panic/panic concurrency/simple pthread-threadname libc-getentropy libc-getrandom libc-misc libc-fs atomic env align
     MIRI_TEST_TARGET=aarch64-linux-android run_tests_minimal hello integer vec panic/panic
     MIRI_TEST_TARGET=wasm32-wasi run_tests_minimal no_std integer strings wasm