From 4d5305644958f2d9b79777c4f448eb93ab2b0c52 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Tue, 30 Sep 2025 00:54:22 +0300
Subject: [PATCH 01/16] Add feature for Wasm Exnref support and separate test
 skips for legacy vs Exnref EH skipping.

---
 .circleci/config.yml     |  6 ++++--
 src/settings_internal.js |  6 +++++-
 test/common.py           | 21 ++++++++++++---------
 tools/feature_matrix.py  | 24 +++++++++++++++++++++++-
 4 files changed, 44 insertions(+), 13 deletions(-)

diff --git a/.circleci/config.yml b/.circleci/config.yml
index efecb37504ff0..23c5aee8c2d63 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -1194,7 +1194,8 @@ jobs:
       # https://github.com/emscripten-core/emscripten/pull/11382#pullrequestreview-428902638
       EMTEST_LACKS_NATIVE_CLANG: "1"
       EMTEST_SKIP_V8: "1"
-      EMTEST_SKIP_EH: "1"
+      EMTEST_SKIP_WASM_LEGACY_EH: "1"
+      EMTEST_SKIP_WASM_EXNREF_EH: "1"
       EMTEST_SKIP_WASM64: "1"
       EMTEST_SKIP_SCONS: "1"
       EMTEST_SKIP_RUST: "1"
@@ -1230,7 +1231,8 @@ jobs:
       # We don't install d8 or modern node on the mac runner so we skip any
       # tests that depend on those.
       EMTEST_SKIP_V8: "1"
-      EMTEST_SKIP_EH: "1"
+      EMTEST_SKIP_WASM_LEGACY_EH: "1"
+      EMTEST_SKIP_WASM_EXNREF_EH: "1"
       EMTEST_SKIP_WASM64: "1"
       EMTEST_SKIP_SCONS: "1"
       EMTEST_SKIP_RUST: "1"
diff --git a/src/settings_internal.js b/src/settings_internal.js
index 1c16446953d68..5e1d2cb151d4f 100644
--- a/src/settings_internal.js
+++ b/src/settings_internal.js
@@ -180,7 +180,11 @@ var CAN_ADDRESS_2GB = false;
 // This has no effect if DWARF is not being emitted.
 var SEPARATE_DWARF = false;
 
-// New WebAssembly exception handling
+// Target WebAssembly exception handling instead of JavaScript-side exception
+// handling. Furthermore, if WASM_LEGACY_EXCEPTIONS=1, then old legacy Wasm
+// exception handling is used, and if WASM_LEGACY_EXCEPTIONS=0, then new Wasm
+// Exnref exception handling is targeted.
+// Enabled by passing -fwasm-exceptions on the command line.
 var WASM_EXCEPTIONS = false;
 
 // Set to true if the program has a main function.  By default this is
diff --git a/test/common.py b/test/common.py
index 86ccb115df7c8..e7fd0d2561939 100644
--- a/test/common.py
+++ b/test/common.py
@@ -1207,18 +1207,21 @@ def require_wasm_legacy_eh(self):
       self.js_engines = [v8]
       return
 
-    if 'EMTEST_SKIP_EH' in os.environ:
-      self.skipTest('test requires node >= 17 or d8 (and EMTEST_SKIP_EH is set)')
+    if 'EMTEST_SKIP_WASM_LEGACY_EH' in os.environ:
+      self.skipTest('test requires node >= 17 or d8 (and EMTEST_SKIP_WASM_LEGACY_EH is set)')
     else:
-      self.fail('either d8 or node >= 17 required to run wasm-eh tests.  Use EMTEST_SKIP_EH to skip')
+      self.fail('either d8 or node >= 17 required to run legacy wasm-eh tests.  Use EMTEST_SKIP_WASM_LEGACY_EH to skip')
 
   def require_wasm_eh(self):
     self.set_setting('WASM_LEGACY_EXCEPTIONS', 0)
-    if self.try_require_node_version(24):
-      self.node_args.append('--experimental-wasm-exnref')
-      return
 
     if self.is_browser_test():
+      if 'EMTEST_SKIP_WASM_EXNREF_EH' in os.environ:
+        self.skipTest('test requires a browser with new Exnref Wasm exceptions support (and EMTEST_SKIP_WASM_EXNREF_EH is set)')
+      return
+
+    if self.try_require_node_version(24):
+      self.node_args.append('--experimental-wasm-exnref')
       return
 
     v8 = self.get_v8()
@@ -1228,10 +1231,10 @@ def require_wasm_eh(self):
       self.v8_args.append('--experimental-wasm-exnref')
       return
 
-    if 'EMTEST_SKIP_EH' in os.environ:
-      self.skipTest('test requires node v24 or d8 (and EMTEST_SKIP_EH is set)')
+    if 'EMTEST_SKIP_WASM_EXNREF_EH' in os.environ:
+      self.skipTest('test requires node v24 or d8 (and EMTEST_SKIP_WASM_EXNREF_EH is set)')
     else:
-      self.fail('either d8 or node v24 required to run wasm-eh tests.  Use EMTEST_SKIP_EH to skip')
+      self.fail('either d8 or node v24 required to run Exnref wasm-eh tests.  Use EMTEST_SKIP_WASM_EXNREF_EH to skip')
 
   def require_jspi(self):
     # emcc warns about stack switching being experimental, and we build with
diff --git a/tools/feature_matrix.py b/tools/feature_matrix.py
index 405529e1fcda4..aad1a6431ccf0 100644
--- a/tools/feature_matrix.py
+++ b/tools/feature_matrix.py
@@ -39,6 +39,8 @@ class Feature(IntEnum):
   PROMISE_ANY = auto()
   MEMORY64 = auto()
   WORKER_ES6_MODULES = auto()
+  WASM_LEGACY_EXCEPTIONS = auto()
+  WASM_EXNREF_EXCEPTIONS = auto()
 
 
 disable_override_features = set()
@@ -95,6 +97,22 @@ class Feature(IntEnum):
     'safari': 150000,
     'node': 0, # This is a browser only feature, no requirements on Node.js
   },
+  # Legacy Wasm exceptions was the first (now legacy) format for native exception
+  # handling in WebAssembly.
+  Feature.WASM_LEGACY_EXCEPTIONS: {
+    'chrome': 95,
+    'firefox': 100,
+    'safari': 150200,
+    'node': 170000,
+  },
+  # Exnref Wasm exceptions is a newer format for native exception handling in
+  # WebAssembly.
+  Feature.WASM_EXNREF_EXCEPTIONS: {
+    'chrome': 137,
+    'firefox': 131,
+    'safari': 180400,
+    'node': 240000, # Supported with flag --experimental-wasm-exnref (TODO: Change this to unflagged version once it ships)
+  },
 }
 
 # Static assertion to check that we actually need each of the above feature flags
@@ -155,7 +173,7 @@ def enable_feature(feature, reason, override=False):
         diagnostics.warning(
             'compatibility',
             f'{name}={user_settings[name]} is not compatible with {reason} '
-            f'({min_version} or above required)')
+            f'({name}={min_version} or above required)')
       else:
         # If no conflict, bump the minimum version to accommodate the feature.
         setattr(settings, name, min_version)
@@ -186,3 +204,7 @@ def apply_min_browser_versions():
     enable_feature(Feature.WORKER_ES6_MODULES, 'EXPORT_ES6 with -pthread')
   if settings.EXPORT_ES6 and settings.WASM_WORKERS:
     enable_feature(Feature.WORKER_ES6_MODULES, 'EXPORT_ES6 with -sWASM_WORKERS')
+  if settings.WASM_EXCEPTIONS and settings.WASM_LEGACY_EXCEPTIONS:
+    enable_feature(Feature.WASM_LEGACY_EXCEPTIONS, '-fwasm-exceptions')
+  if not settings.WASM_LEGACY_EXCEPTIONS:
+    enable_feature(Feature.WASM_EXNREF_EXCEPTIONS, '-sWASM_LEGACY_EXCEPTIONS=0')

From 68e26e3744db01c629ad7c047a7b5007739b3cdc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Tue, 30 Sep 2025 01:16:52 +0300
Subject: [PATCH 02/16] code size

---
 test/codesize/test_codesize_cxx_except_wasm.json | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/test/codesize/test_codesize_cxx_except_wasm.json b/test/codesize/test_codesize_cxx_except_wasm.json
index b6fe6f9ed1f94..a376eb1110b0e 100644
--- a/test/codesize/test_codesize_cxx_except_wasm.json
+++ b/test/codesize/test_codesize_cxx_except_wasm.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 19608,
-  "a.out.js.gz": 8109,
+  "a.out.js": 19539,
+  "a.out.js.gz": 8086,
   "a.out.nodebug.wasm": 144630,
   "a.out.nodebug.wasm.gz": 54894,
-  "total": 164238,
-  "total_gz": 63003,
+  "total": 164169,
+  "total_gz": 62980,
   "sent": [
     "_abort_js",
     "_tzset_js",

From 36bd04822303ce7ee2698272ac2796d065e2ed13 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Tue, 30 Sep 2025 01:34:17 +0300
Subject: [PATCH 03/16] Fix merge

---
 tools/feature_matrix.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tools/feature_matrix.py b/tools/feature_matrix.py
index 8a2d792fc4e40..17afd99b9dad4 100644
--- a/tools/feature_matrix.py
+++ b/tools/feature_matrix.py
@@ -106,6 +106,7 @@ class Feature(IntEnum):
     'firefox': 105,
     'safari': 170000,
     'node': 0, # This is a browser only feature, no requirements on Node.js
+  },
   # Legacy Wasm exceptions was the first (now legacy) format for native exception
   # handling in WebAssembly.
   Feature.WASM_LEGACY_EXCEPTIONS: {

From 32dfa3d40d416dfa69f16d093d4fa6dcf7cf774f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Tue, 30 Sep 2025 02:54:06 +0300
Subject: [PATCH 04/16] Fix test expectation

---
 test/test_other.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/test_other.py b/test/test_other.py
index 51359ae62637a..5440fd82345ac 100644
--- a/test/test_other.py
+++ b/test/test_other.py
@@ -14314,10 +14314,10 @@ def test_reproduce(self):
 
   def test_min_browser_version(self):
     err = self.expect_fail([EMCC, test_file('hello_world.c'), '-Wno-transpile', '-Werror', '-sWASM_BIGINT', '-sMIN_SAFARI_VERSION=130000'])
-    self.assertContained('emcc: error: MIN_SAFARI_VERSION=130000 is not compatible with WASM_BIGINT (150000 or above required)', err)
+    self.assertContained('emcc: error: MIN_SAFARI_VERSION=130000 is not compatible with WASM_BIGINT (MIN_SAFARI_VERSION=150000 or above required)', err)
 
     err = self.expect_fail([EMCC, test_file('hello_world.c'), '-Wno-transpile', '-Werror', '-pthread', '-sMIN_FIREFOX_VERSION=65'])
-    self.assertContained('emcc: error: MIN_FIREFOX_VERSION=65 is not compatible with pthreads (79 or above required)', err)
+    self.assertContained('emcc: error: MIN_FIREFOX_VERSION=65 is not compatible with pthreads (MIN_FIREFOX_VERSION=79 or above required)', err)
 
   def test_signext_lowering(self):
     # Use `-v` to show the sub-commands being run by emcc.

From d499c8aef3d4116419be0d8fe41c11c75b48ae32 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Tue, 30 Sep 2025 03:29:51 +0300
Subject: [PATCH 05/16] 80column

---
 tools/feature_matrix.py | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/tools/feature_matrix.py b/tools/feature_matrix.py
index 17afd99b9dad4..cf68d0aaa7410 100644
--- a/tools/feature_matrix.py
+++ b/tools/feature_matrix.py
@@ -107,8 +107,8 @@ class Feature(IntEnum):
     'safari': 170000,
     'node': 0, # This is a browser only feature, no requirements on Node.js
   },
-  # Legacy Wasm exceptions was the first (now legacy) format for native exception
-  # handling in WebAssembly.
+  # Legacy Wasm exceptions was the first (now legacy) format for native
+  # exception handling in WebAssembly.
   Feature.WASM_LEGACY_EXCEPTIONS: {
     'chrome': 95,
     'firefox': 100,
@@ -121,7 +121,9 @@ class Feature(IntEnum):
     'chrome': 137,
     'firefox': 131,
     'safari': 180400,
-    'node': 240000, # Supported with flag --experimental-wasm-exnref (TODO: Change this to unflagged version once it ships)
+    # Supported with flag --experimental-wasm-exnref (TODO: Change this to
+    # unflagged version of Node.js that ships exnref default-on)
+    'node': 240000,
   },
 }
 

From fa2dc4fe3d0ab962e00e3e8661e7b5c0372942aa Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Tue, 30 Sep 2025 03:42:20 +0300
Subject: [PATCH 06/16] code size

---
 test/codesize/test_codesize_cxx_except_wasm.json | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/test/codesize/test_codesize_cxx_except_wasm.json b/test/codesize/test_codesize_cxx_except_wasm.json
index 95b6cf3994be4..fd85059c9698d 100644
--- a/test/codesize/test_codesize_cxx_except_wasm.json
+++ b/test/codesize/test_codesize_cxx_except_wasm.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 19563,
-  "a.out.js.gz": 8103,
+  "a.out.js": 19494,
+  "a.out.js.gz": 8083,
   "a.out.nodebug.wasm": 144630,
   "a.out.nodebug.wasm.gz": 54894,
-  "total": 164193,
-  "total_gz": 62997,
+  "total": 164124,
+  "total_gz": 62977,
   "sent": [
     "_abort_js",
     "_tzset_js",

From 4dcf581e66e30636cf262304aeb5253fa4609102 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Tue, 30 Sep 2025 15:21:03 +0300
Subject: [PATCH 07/16] Update feature_matrix check

---
 tools/feature_matrix.py | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/tools/feature_matrix.py b/tools/feature_matrix.py
index cf68d0aaa7410..be54a3ee3b3b7 100644
--- a/tools/feature_matrix.py
+++ b/tools/feature_matrix.py
@@ -220,6 +220,6 @@ def apply_min_browser_versions():
   if settings.OFFSCREENCANVAS_SUPPORT:
     enable_feature(Feature.OFFSCREENCANVAS_SUPPORT, 'OFFSCREENCANVAS_SUPPORT')
   if settings.WASM_EXCEPTIONS and settings.WASM_LEGACY_EXCEPTIONS:
-    enable_feature(Feature.WASM_LEGACY_EXCEPTIONS, '-fwasm-exceptions')
-  if not settings.WASM_LEGACY_EXCEPTIONS:
-    enable_feature(Feature.WASM_EXNREF_EXCEPTIONS, '-sWASM_LEGACY_EXCEPTIONS=0')
+    enable_feature(Feature.WASM_LEGACY_EXCEPTIONS, 'Wasm Legacy exceptions (-fwasm-exceptions with -sWASM_LEGACY_EXCEPTIONS=1)')
+  if settings.WASM_EXCEPTIONS and not settings.WASM_LEGACY_EXCEPTIONS:
+    enable_feature(Feature.WASM_EXNREF_EXCEPTIONS, 'Wasm Exnref exceptions (-fwasm-exceptions with -sWASM_LEGACY_EXCEPTIONS=0)')

From 3ab97c9db5320429ca8afc6671f5918a9ca43c0e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Tue, 30 Sep 2025 15:36:33 +0300
Subject: [PATCH 08/16] Do not use the word Exnref to refer to Wasm exception
 handling.

---
 .circleci/config.yml     |  4 ++--
 ChangeLog.md             |  2 +-
 src/settings_internal.js |  4 ++--
 test/common.py           | 10 +++++-----
 test/test_other.py       |  2 +-
 tools/feature_matrix.py  | 12 +++++++-----
 6 files changed, 18 insertions(+), 16 deletions(-)

diff --git a/.circleci/config.yml b/.circleci/config.yml
index 23c5aee8c2d63..9d5e6ddbe9992 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -1195,7 +1195,7 @@ jobs:
       EMTEST_LACKS_NATIVE_CLANG: "1"
       EMTEST_SKIP_V8: "1"
       EMTEST_SKIP_WASM_LEGACY_EH: "1"
-      EMTEST_SKIP_WASM_EXNREF_EH: "1"
+      EMTEST_SKIP_EH: "1"
       EMTEST_SKIP_WASM64: "1"
       EMTEST_SKIP_SCONS: "1"
       EMTEST_SKIP_RUST: "1"
@@ -1232,7 +1232,7 @@ jobs:
       # tests that depend on those.
       EMTEST_SKIP_V8: "1"
       EMTEST_SKIP_WASM_LEGACY_EH: "1"
-      EMTEST_SKIP_WASM_EXNREF_EH: "1"
+      EMTEST_SKIP_EH: "1"
       EMTEST_SKIP_WASM64: "1"
       EMTEST_SKIP_SCONS: "1"
       EMTEST_SKIP_RUST: "1"
diff --git a/ChangeLog.md b/ChangeLog.md
index 880a74f4757c5..36d0851c10517 100644
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -317,7 +317,7 @@ See docs/process.md for more on how version tagging works.
 - Emscripten version was bumped to 4.0.0. Happy new year, happy new major
   version!  While version has a few interesting changes, there is nothing huge
   that makes it different from any other release. (#19053)
-- `-sWASM_LEAGCY_EXCEPTIONS` option is added. (#23365) If true, it will emit
+- `-sWASM_LEGACY_EXCEPTIONS` option is added. (#23365) If true, it will emit
   instructions for the legacy Wasm exception handling proposal
   (https://github.com/WebAssembly/exception-handling/blob/main/proposals/exception-handling/legacy/Exceptions.md),
   and if false, the new standardized exception handling proposal
diff --git a/src/settings_internal.js b/src/settings_internal.js
index 5e1d2cb151d4f..2f81a0ea647fc 100644
--- a/src/settings_internal.js
+++ b/src/settings_internal.js
@@ -182,8 +182,8 @@ var SEPARATE_DWARF = false;
 
 // Target WebAssembly exception handling instead of JavaScript-side exception
 // handling. Furthermore, if WASM_LEGACY_EXCEPTIONS=1, then old legacy Wasm
-// exception handling is used, and if WASM_LEGACY_EXCEPTIONS=0, then new Wasm
-// Exnref exception handling is targeted.
+// exception handling is used, and if WASM_LEGACY_EXCEPTIONS=0, then Wasm
+// exception handling is targeted.
 // Enabled by passing -fwasm-exceptions on the command line.
 var WASM_EXCEPTIONS = false;
 
diff --git a/test/common.py b/test/common.py
index e7fd0d2561939..78c6bf4fcdf28 100644
--- a/test/common.py
+++ b/test/common.py
@@ -1216,8 +1216,8 @@ def require_wasm_eh(self):
     self.set_setting('WASM_LEGACY_EXCEPTIONS', 0)
 
     if self.is_browser_test():
-      if 'EMTEST_SKIP_WASM_EXNREF_EH' in os.environ:
-        self.skipTest('test requires a browser with new Exnref Wasm exceptions support (and EMTEST_SKIP_WASM_EXNREF_EH is set)')
+      if 'EMTEST_SKIP_EH' in os.environ:
+        self.skipTest('test requires a browser with Wasm exceptions support (and EMTEST_SKIP_EH is set)')
       return
 
     if self.try_require_node_version(24):
@@ -1231,10 +1231,10 @@ def require_wasm_eh(self):
       self.v8_args.append('--experimental-wasm-exnref')
       return
 
-    if 'EMTEST_SKIP_WASM_EXNREF_EH' in os.environ:
-      self.skipTest('test requires node v24 or d8 (and EMTEST_SKIP_WASM_EXNREF_EH is set)')
+    if 'EMTEST_SKIP_EH' in os.environ:
+      self.skipTest('test requires node v24 or d8 (and EMTEST_SKIP_EH is set)')
     else:
-      self.fail('either d8 or node v24 required to run Exnref wasm-eh tests.  Use EMTEST_SKIP_WASM_EXNREF_EH to skip')
+      self.fail('either d8 or node v24 required to run wasm-eh tests.  Use EMTEST_SKIP_EH to skip')
 
   def require_jspi(self):
     # emcc warns about stack switching being experimental, and we build with
diff --git a/test/test_other.py b/test/test_other.py
index 5440fd82345ac..c8b822b596831 100644
--- a/test/test_other.py
+++ b/test/test_other.py
@@ -3633,7 +3633,7 @@ def test_embind_tsgen_jspi(self):
   })
   def test_embind_tsgen_exceptions(self, legacy):
     if not legacy and shared.get_node_version(config.NODE_JS)[0] < 22:
-      self.skipTest('Node version needs to be 22 or greater to run tsgen with exnref')
+      self.skipTest('Node version needs to be 22 or greater to run tsgen with Wasm EH')
     self.set_setting('WASM_LEGACY_EXCEPTIONS', legacy)
 
     # Check that when Wasm exceptions and assertions are enabled bindings still generate.
diff --git a/tools/feature_matrix.py b/tools/feature_matrix.py
index be54a3ee3b3b7..b80eae11c17d7 100644
--- a/tools/feature_matrix.py
+++ b/tools/feature_matrix.py
@@ -41,7 +41,7 @@ class Feature(IntEnum):
   WORKER_ES6_MODULES = auto()
   OFFSCREENCANVAS_SUPPORT = auto()
   WASM_LEGACY_EXCEPTIONS = auto()
-  WASM_EXNREF_EXCEPTIONS = auto()
+  WASM_EXCEPTIONS = auto()
 
 
 disable_override_features = set()
@@ -115,14 +115,16 @@ class Feature(IntEnum):
     'safari': 150200,
     'node': 170000,
   },
-  # Exnref Wasm exceptions is a newer format for native exception handling in
+  # Wasm exceptions is a newer format for native exception handling in
   # WebAssembly.
-  Feature.WASM_EXNREF_EXCEPTIONS: {
+  Feature.WASM_EXCEPTIONS: {
     'chrome': 137,
     'firefox': 131,
     'safari': 180400,
     # Supported with flag --experimental-wasm-exnref (TODO: Change this to
-    # unflagged version of Node.js that ships exnref default-on)
+    # unflagged version of Node.js 260000 that ships Wasm EH enabled, after
+    # Emscripten unit testing has migrated to Node.js 26, and Emsdk ships
+    # Node.js 26)
     'node': 240000,
   },
 }
@@ -222,4 +224,4 @@ def apply_min_browser_versions():
   if settings.WASM_EXCEPTIONS and settings.WASM_LEGACY_EXCEPTIONS:
     enable_feature(Feature.WASM_LEGACY_EXCEPTIONS, 'Wasm Legacy exceptions (-fwasm-exceptions with -sWASM_LEGACY_EXCEPTIONS=1)')
   if settings.WASM_EXCEPTIONS and not settings.WASM_LEGACY_EXCEPTIONS:
-    enable_feature(Feature.WASM_EXNREF_EXCEPTIONS, 'Wasm Exnref exceptions (-fwasm-exceptions with -sWASM_LEGACY_EXCEPTIONS=0)')
+    enable_feature(Feature.WASM_EXCEPTIONS, 'Wasm exceptions (-fwasm-exceptions with -sWASM_LEGACY_EXCEPTIONS=0)')

From c003d0c46fa9625822815a792d387a0acd8e91ba Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Tue, 30 Sep 2025 18:28:22 +0300
Subject: [PATCH 09/16] Make SUPPORT_LONGJMP imply Wasm Exceptions

---
 tools/feature_matrix.py | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/tools/feature_matrix.py b/tools/feature_matrix.py
index b80eae11c17d7..7b2051495b829 100644
--- a/tools/feature_matrix.py
+++ b/tools/feature_matrix.py
@@ -221,7 +221,8 @@ def apply_min_browser_versions():
     enable_feature(Feature.WORKER_ES6_MODULES, 'EXPORT_ES6 with -sWASM_WORKERS')
   if settings.OFFSCREENCANVAS_SUPPORT:
     enable_feature(Feature.OFFSCREENCANVAS_SUPPORT, 'OFFSCREENCANVAS_SUPPORT')
-  if settings.WASM_EXCEPTIONS and settings.WASM_LEGACY_EXCEPTIONS:
-    enable_feature(Feature.WASM_LEGACY_EXCEPTIONS, 'Wasm Legacy exceptions (-fwasm-exceptions with -sWASM_LEGACY_EXCEPTIONS=1)')
-  if settings.WASM_EXCEPTIONS and not settings.WASM_LEGACY_EXCEPTIONS:
-    enable_feature(Feature.WASM_EXCEPTIONS, 'Wasm exceptions (-fwasm-exceptions with -sWASM_LEGACY_EXCEPTIONS=0)')
+  if settings.WASM_EXCEPTIONS or settings.SUPPORT_LONGJMP == 'wasm': # Wasm longjmp support will lean on Wasm (Legacy) EH
+    if settings.WASM_LEGACY_EXCEPTIONS:
+      enable_feature(Feature.WASM_LEGACY_EXCEPTIONS, 'Wasm Legacy exceptions (-fwasm-exceptions with -sWASM_LEGACY_EXCEPTIONS=1)')
+    else:
+      enable_feature(Feature.WASM_EXCEPTIONS, 'Wasm exceptions (-fwasm-exceptions with -sWASM_LEGACY_EXCEPTIONS=0)')

From 351e67af73f296ee6566c2ae8b21d68e9bc782cf Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Tue, 30 Sep 2025 18:40:49 +0300
Subject: [PATCH 10/16] When user passes EMTEST_SKIP_(WASM_LEGACY_)EH=1, then
 do skip the tests, even if current environment would support them.

---
 test/common.py | 17 +++++++----------
 1 file changed, 7 insertions(+), 10 deletions(-)

diff --git a/test/common.py b/test/common.py
index 78c6bf4fcdf28..ae198aafa31be 100644
--- a/test/common.py
+++ b/test/common.py
@@ -1197,6 +1197,9 @@ def require_simd(self):
       self.fail('either d8 or node >= 16 required to run wasm64 tests.  Use EMTEST_SKIP_SIMD to skip')
 
   def require_wasm_legacy_eh(self):
+    if 'EMTEST_SKIP_WASM_LEGACY_EH' in os.environ:
+      self.skipTest('test requires node >= 17 or d8 (and EMTEST_SKIP_WASM_LEGACY_EH is set)')
+
     self.set_setting('WASM_LEGACY_EXCEPTIONS')
     if self.try_require_node_version(17):
       return
@@ -1207,17 +1210,14 @@ def require_wasm_legacy_eh(self):
       self.js_engines = [v8]
       return
 
-    if 'EMTEST_SKIP_WASM_LEGACY_EH' in os.environ:
-      self.skipTest('test requires node >= 17 or d8 (and EMTEST_SKIP_WASM_LEGACY_EH is set)')
-    else:
-      self.fail('either d8 or node >= 17 required to run legacy wasm-eh tests.  Use EMTEST_SKIP_WASM_LEGACY_EH to skip')
+    self.fail('either d8 or node >= 17 required to run legacy wasm-eh tests.  Use EMTEST_SKIP_WASM_LEGACY_EH to skip')
 
   def require_wasm_eh(self):
+    if 'EMTEST_SKIP_EH' in os.environ:
+      self.skipTest('test requires a browser with Wasm exceptions support (and EMTEST_SKIP_EH is set)')
     self.set_setting('WASM_LEGACY_EXCEPTIONS', 0)
 
     if self.is_browser_test():
-      if 'EMTEST_SKIP_EH' in os.environ:
-        self.skipTest('test requires a browser with Wasm exceptions support (and EMTEST_SKIP_EH is set)')
       return
 
     if self.try_require_node_version(24):
@@ -1231,10 +1231,7 @@ def require_wasm_eh(self):
       self.v8_args.append('--experimental-wasm-exnref')
       return
 
-    if 'EMTEST_SKIP_EH' in os.environ:
-      self.skipTest('test requires node v24 or d8 (and EMTEST_SKIP_EH is set)')
-    else:
-      self.fail('either d8 or node v24 required to run wasm-eh tests.  Use EMTEST_SKIP_EH to skip')
+    self.fail('either d8 or node v24 required to run wasm-eh tests.  Use EMTEST_SKIP_EH to skip')
 
   def require_jspi(self):
     # emcc warns about stack switching being experimental, and we build with

From 1911a9165664e930c0bbe2c07ad765c1f9350692 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Wed, 1 Oct 2025 02:44:48 +0300
Subject: [PATCH 11/16] codesize

---
 test/codesize/test_codesize_cxx_except_wasm.json | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/test/codesize/test_codesize_cxx_except_wasm.json b/test/codesize/test_codesize_cxx_except_wasm.json
index fd85059c9698d..153a065b82db9 100644
--- a/test/codesize/test_codesize_cxx_except_wasm.json
+++ b/test/codesize/test_codesize_cxx_except_wasm.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 19494,
-  "a.out.js.gz": 8083,
+  "a.out.js": 19492,
+  "a.out.js.gz": 8078,
   "a.out.nodebug.wasm": 144630,
   "a.out.nodebug.wasm.gz": 54894,
-  "total": 164124,
-  "total_gz": 62977,
+  "total": 164122,
+  "total_gz": 62972,
   "sent": [
     "_abort_js",
     "_tzset_js",

From 6047664293f9184400fe48163197a861f9003cde Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Wed, 1 Oct 2025 21:46:01 +0300
Subject: [PATCH 12/16] Fix bad git automerge

---
 test/common.py | 30 +++++++++++++++---------------
 1 file changed, 15 insertions(+), 15 deletions(-)

diff --git a/test/common.py b/test/common.py
index 54a129f7ea1f5..0e15f0d83719d 100644
--- a/test/common.py
+++ b/test/common.py
@@ -211,18 +211,18 @@ def skip_if_simple(name, condition, note=''):
   assert not callable(note)
 
   def decorator(func):
-  assert callable(func)
+    assert callable(func)
 
-  @wraps(func)
-  def decorated(self, *args, **kwargs):
-      if condition(self):
-        explanation_str = name
-        if note:
-          explanation_str += ': %s' % note
-        self.skipTest(explanation_str)
-    return func(self, *args, **kwargs)
+    @wraps(func)
+    def decorated(self, *args, **kwargs):
+        if condition(self):
+          explanation_str = name
+          if note:
+            explanation_str += ': %s' % note
+          self.skipTest(explanation_str)
+      return func(self, *args, **kwargs)
 
-  return decorated
+    return decorated
 
   return decorator
 
@@ -1044,7 +1044,7 @@ def require_v8(self):
       self.skipTest('test requires v8 and EMTEST_SKIP_V8 is set')
     v8 = self.get_v8()
     if not v8:
-        self.fail('d8 required to run this test.  Use EMTEST_SKIP_V8 to skip')
+      self.fail('d8 required to run this test.  Use EMTEST_SKIP_V8 to skip')
     self.require_engine(v8)
     self.cflags.append('-sENVIRONMENT=shell')
 
@@ -1059,7 +1059,7 @@ def require_node(self):
       self.skipTest('test requires node and EMTEST_SKIP_NODE is set')
     nodejs = self.get_nodejs()
     if not nodejs:
-        self.fail('node required to run this test.  Use EMTEST_SKIP_NODE to skip')
+      self.fail('node required to run this test.  Use EMTEST_SKIP_NODE to skip')
     self.require_engine(nodejs)
     return nodejs
 
@@ -1074,7 +1074,7 @@ def require_node_canary(self):
       self.require_engine(nodejs)
       return
 
-      self.fail('node canary required to run this test.  Use EMTEST_SKIP_NODE_CANARY to skip')
+    self.fail('node canary required to run this test.  Use EMTEST_SKIP_NODE_CANARY to skip')
 
   def require_engine(self, engine):
     logger.debug(f'require_engine: {engine}')
@@ -1099,7 +1099,7 @@ def require_wasm64(self):
       self.js_engines = [v8]
       return
 
-      self.fail('either d8 or node >= 24 required to run wasm64 tests.  Use EMTEST_SKIP_WASM64 to skip')
+    self.fail('either d8 or node >= 24 required to run wasm64 tests.  Use EMTEST_SKIP_WASM64 to skip')
 
   def try_require_node_version(self, major, minor = 0, revision = 0):
     nodejs = self.get_nodejs()
@@ -1127,7 +1127,7 @@ def require_simd(self):
       self.js_engines = [v8]
       return
 
-      self.fail('either d8 or node >= 16 required to run wasm64 tests.  Use EMTEST_SKIP_SIMD to skip')
+    self.fail('either d8 or node >= 16 required to run wasm64 tests.  Use EMTEST_SKIP_SIMD to skip')
 
   def require_wasm_legacy_eh(self):
     if 'EMTEST_SKIP_WASM_LEGACY_EH' in os.environ:

From 860c50d46413a4a0749e8af61bed72011092ef54 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Wed, 1 Oct 2025 21:46:30 +0300
Subject: [PATCH 13/16] Fix bad git automerge

---
 test/common.py | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/test/common.py b/test/common.py
index 0e15f0d83719d..734e6d1b45dc7 100644
--- a/test/common.py
+++ b/test/common.py
@@ -215,11 +215,11 @@ def decorator(func):
 
     @wraps(func)
     def decorated(self, *args, **kwargs):
-        if condition(self):
-          explanation_str = name
-          if note:
-            explanation_str += ': %s' % note
-          self.skipTest(explanation_str)
+      if condition(self):
+        explanation_str = name
+        if note:
+          explanation_str += ': %s' % note
+        self.skipTest(explanation_str)
       return func(self, *args, **kwargs)
 
     return decorated

From 458d190ae89c45679ac4abd4a41e5b368e467289 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Wed, 1 Oct 2025 21:47:59 +0300
Subject: [PATCH 14/16] Fix bad git automerge

---
 test/common.py | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/test/common.py b/test/common.py
index 734e6d1b45dc7..fe9cc3731855d 100644
--- a/test/common.py
+++ b/test/common.py
@@ -1149,14 +1149,13 @@ def require_wasm_eh(self):
     if 'EMTEST_SKIP_EH' in os.environ:
       self.skipTest('test requires node v24 or d8 (and EMTEST_SKIP_EH is set)')
     self.set_setting('WASM_LEGACY_EXCEPTIONS', 0)
-
-    if self.is_browser_test():
-      return
-
     if self.try_require_node_version(24):
       self.node_args.append('--experimental-wasm-exnref')
       return
 
+    if self.is_browser_test():
+      return
+
     v8 = self.get_v8()
     if v8:
       self.cflags.append('-sENVIRONMENT=shell')
@@ -1194,7 +1193,7 @@ def require_jspi(self):
       self.v8_args += exp_args
       return
 
-      self.fail('either d8 or node v24 required to run JSPI tests.  Use EMTEST_SKIP_JSPI to skip')
+    self.fail('either d8 or node v24 required to run JSPI tests.  Use EMTEST_SKIP_JSPI to skip')
 
   def require_wasm2js(self):
     if self.is_wasm64():

From 9fcd1b94dd2ca7fca58f92e83b4e5b4ba11b6ee6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Thu, 2 Oct 2025 00:26:41 +0300
Subject: [PATCH 15/16] codesize

---
 test/codesize/test_codesize_cxx_except_wasm.json | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/test/codesize/test_codesize_cxx_except_wasm.json b/test/codesize/test_codesize_cxx_except_wasm.json
index 153a065b82db9..de9e396eec2ed 100644
--- a/test/codesize/test_codesize_cxx_except_wasm.json
+++ b/test/codesize/test_codesize_cxx_except_wasm.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 19492,
-  "a.out.js.gz": 8078,
+  "a.out.js": 19486,
+  "a.out.js.gz": 8077,
   "a.out.nodebug.wasm": 144630,
   "a.out.nodebug.wasm.gz": 54894,
-  "total": 164122,
-  "total_gz": 62972,
+  "total": 164116,
+  "total_gz": 62971,
   "sent": [
     "_abort_js",
     "_tzset_js",

From 9b89c2c259325d5d8fb6eba132ddb364c91da5df Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Thu, 2 Oct 2025 01:42:29 +0300
Subject: [PATCH 16/16] Rename EMTEST_SKIP_EH to EMTEST_SKIP_WASM_EH

---
 .circleci/config.yml | 4 ++--
 test/common.py       | 6 +++---
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/.circleci/config.yml b/.circleci/config.yml
index 149d60a0c1a43..179ea692e2954 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -1191,7 +1191,7 @@ jobs:
       EMTEST_LACKS_NATIVE_CLANG: "1"
       EMTEST_SKIP_V8: "1"
       EMTEST_SKIP_WASM_LEGACY_EH: "1"
-      EMTEST_SKIP_EH: "1"
+      EMTEST_SKIP_WASM_EH: "1"
       EMTEST_SKIP_WASM64: "1"
       EMTEST_SKIP_SCONS: "1"
       EMTEST_SKIP_RUST: "1"
@@ -1228,7 +1228,7 @@ jobs:
       # tests that depend on those.
       EMTEST_SKIP_V8: "1"
       EMTEST_SKIP_WASM_LEGACY_EH: "1"
-      EMTEST_SKIP_EH: "1"
+      EMTEST_SKIP_WASM_EH: "1"
       EMTEST_SKIP_WASM64: "1"
       EMTEST_SKIP_SCONS: "1"
       EMTEST_SKIP_RUST: "1"
diff --git a/test/common.py b/test/common.py
index fe9cc3731855d..22e53ba39640a 100644
--- a/test/common.py
+++ b/test/common.py
@@ -1146,8 +1146,8 @@ def require_wasm_legacy_eh(self):
     self.fail('either d8 or node >= 17 required to run legacy wasm-eh tests.  Use EMTEST_SKIP_WASM_LEGACY_EH to skip')
 
   def require_wasm_eh(self):
-    if 'EMTEST_SKIP_EH' in os.environ:
-      self.skipTest('test requires node v24 or d8 (and EMTEST_SKIP_EH is set)')
+    if 'EMTEST_SKIP_WASM_EH' in os.environ:
+      self.skipTest('test requires node v24 or d8 (and EMTEST_SKIP_WASM_EH is set)')
     self.set_setting('WASM_LEGACY_EXCEPTIONS', 0)
     if self.try_require_node_version(24):
       self.node_args.append('--experimental-wasm-exnref')
@@ -1163,7 +1163,7 @@ def require_wasm_eh(self):
       self.v8_args.append('--experimental-wasm-exnref')
       return
 
-    self.fail('either d8 or node v24 required to run wasm-eh tests.  Use EMTEST_SKIP_EH to skip')
+    self.fail('either d8 or node v24 required to run wasm-eh tests.  Use EMTEST_SKIP_WASM_EH to skip')
 
   def require_jspi(self):
     if 'EMTEST_SKIP_JSPI' in os.environ: