From e47712c900ca2190c308b89b8e62dac25ce239ed Mon Sep 17 00:00:00 2001
From: Brett Cannon <brett@python.org>
Date: Wed, 27 Aug 2025 11:03:26 -0700
Subject: [PATCH 1/3] GH-95952: Require setting `HOSTRUNNER` when cross
 compiling for WASI macOS by default doesn't have the requisite CLI tools to
 make a default value easy. Plus Tools/wasm/wasi takes care of setting
 HOSTRUNNER.

---
 configure    | 6 ++++--
 configure.ac | 7 +++----
 2 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/configure b/configure
index bdeab8a6d126a3..67e4ffd0605397 100755
--- a/configure
+++ b/configure
@@ -7903,8 +7903,10 @@ then :
   as_fn_append HOSTRUNNER " --experimental-wasm-memory64"
 fi
      ;; #(
-              WASI) :
-    HOSTRUNNER='wasmtime run --wasm max-wasm-stack=16777216 --wasi preview2=n --env PYTHONPATH=/$(shell realpath --relative-to $(abs_srcdir) $(abs_builddir))/$(shell cat pybuilddir.txt):/Lib --dir $(srcdir)::/' ;; #(
+  WASI) :
+
+      as_fn_error $? "HOSTRUNNER must be set when cross compiling to WASI" "$LINENO" 5
+     ;; #(
   *) :
     HOSTRUNNER=''
    ;;
diff --git a/configure.ac b/configure.ac
index 991fa40746be78..c4f08550320ff2 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1636,10 +1636,9 @@ then
       HOSTRUNNER="$NODE"
       AS_VAR_IF([host_cpu], [wasm64], [AS_VAR_APPEND([HOSTRUNNER], [" --experimental-wasm-memory64"])])
     ],
-    dnl TODO: support other WASI runtimes
-    dnl wasmtime starts the process with "/" as CWD. For OOT builds add the
-    dnl directory containing _sysconfigdata to PYTHONPATH.
-    [WASI], [HOSTRUNNER='wasmtime run --wasm max-wasm-stack=16777216 --wasi preview2=n --env PYTHONPATH=/$(shell realpath --relative-to $(abs_srcdir) $(abs_builddir))/$(shell cat pybuilddir.txt):/Lib --dir $(srcdir)::/'],
+    [WASI], [
+      AC_MSG_ERROR([HOSTRUNNER must be set when cross compiling to WASI])
+    ],
     [HOSTRUNNER='']
   )
 fi

From 6949eee58b104d8ecd13c56a82189259abc64703 Mon Sep 17 00:00:00 2001
From: Brett Cannon <brett@python.org>
Date: Wed, 27 Aug 2025 11:32:10 -0700
Subject: [PATCH 2/3] Add a news entry

---
 .../next/Build/2025-08-27-11-32-02.gh-issue-95952.KSymc7.rst | 5 +++++
 1 file changed, 5 insertions(+)
 create mode 100644 Misc/NEWS.d/next/Build/2025-08-27-11-32-02.gh-issue-95952.KSymc7.rst

diff --git a/Misc/NEWS.d/next/Build/2025-08-27-11-32-02.gh-issue-95952.KSymc7.rst b/Misc/NEWS.d/next/Build/2025-08-27-11-32-02.gh-issue-95952.KSymc7.rst
new file mode 100644
index 00000000000000..0e4b4615342b24
--- /dev/null
+++ b/Misc/NEWS.d/next/Build/2025-08-27-11-32-02.gh-issue-95952.KSymc7.rst
@@ -0,0 +1,5 @@
+When cross-compiling for WASI, require that the HOSTRUNNER environment
+variable be explicitly set.
+
+This was needed as macOS lacks the appropriate CLI tools to set a reasonable
+default.

From d9a79270086bcc30f9b9137f0ffe0aa5817306c5 Mon Sep 17 00:00:00 2001
From: Brett Cannon <brett@python.org>
Date: Wed, 27 Aug 2025 11:32:40 -0700
Subject: [PATCH 3/3] Use a hyphen

---
 configure    | 2 +-
 configure.ac | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/configure b/configure
index 67e4ffd0605397..7dd333690a3a2c 100755
--- a/configure
+++ b/configure
@@ -7905,7 +7905,7 @@ fi
      ;; #(
   WASI) :
 
-      as_fn_error $? "HOSTRUNNER must be set when cross compiling to WASI" "$LINENO" 5
+      as_fn_error $? "HOSTRUNNER must be set when cross-compiling to WASI" "$LINENO" 5
      ;; #(
   *) :
     HOSTRUNNER=''
diff --git a/configure.ac b/configure.ac
index c4f08550320ff2..8fc8f1eced20cf 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1637,7 +1637,7 @@ then
       AS_VAR_IF([host_cpu], [wasm64], [AS_VAR_APPEND([HOSTRUNNER], [" --experimental-wasm-memory64"])])
     ],
     [WASI], [
-      AC_MSG_ERROR([HOSTRUNNER must be set when cross compiling to WASI])
+      AC_MSG_ERROR([HOSTRUNNER must be set when cross-compiling to WASI])
     ],
     [HOSTRUNNER='']
   )