nodejs: Fix build with ICU 79

ICU 79.1 brings Unicode 18, which adds U+1DF95 LATIN SMALL LIGATURE LONG S WITH DESCENDER S. It case-folds to U+00DF, so for the first time the case closure of a BMP character contains a supplementary code point. V8's gen-regexp-special-case build tool passes every member of that closure to RegExpCaseFolding::Canonicalize(), which asserts a UTF-16 code unit, and aborts with # Check failed: ch <= 0xffff. Backport the V8 fix, adapted to the V8 13.6 bundled with Node.js 24. Signed-off-by: Khem Raj <khem.raj@oss.qualcomm.com>
2026-11-15 04:17:29 +00:00 · 2026-10-30 09:06:23 -07:00
1 parent a6e9171451
commit a5ec41f02d
@@ -0,0 +1,235 @@
+From e455d955bd6b7a7549106d1b9d7ae5bb3b9e77b4 Mon Sep 17 00:00:00 2001
+From: Jakob Linke <jgruber@chromium.org>
+Date: Fri, 9 Oct 2026 12:41:30 +0200
+Subject: [PATCH] v8: [regexp] Handle supplementary case equivalents of BMP
+ characters
+
+Unicode 18 adds U+1DF95, which simple-folds to U+00DF. This creates the
+first case-equivalence class spanning BMP and supplementary characters:
+{U+00DF, U+1E9E, U+1DF95}.
+
+Discard supplementary characters from the generator's non-unicode
+closures before calling Canonicalize, which requires UTF-16 code units
+and otherwise CHECK-fails with ICU 79. Apply the same filtering in
+runtime non-unicode closure.
+
+Generate SupplementaryEquivalentsSet and desugar its BMP characters into
+character classes under /iu and /iv, allowing literals to match
+surrogate pairs.
+
+Backreferences with differing UTF-16 character widths remain unsupported
+and are tracked in crbug.com/571793821.
+
+IgnoreSet is unchanged with ICU 78 and with ICU 78.2 patched to upstream
+Unicode 18 case data. With the patched data, the generator succeeds,
+SupplementaryEquivalentsSet is {U+00DF, U+1E9E}, and regexp tests pass
+in release and debug.
+
+Bug: 571232615, 571668686
+Change-Id: I9eacb273a74c66e17f0cfb1b256e863f2718c130
+Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/8548134
+Reviewed-by: Patrick Thier <pthier@chromium.org>
+Commit-Queue: Jakob Linke <jgruber@chromium.org>
+Cr-Commit-Position: refs/heads/main@{#110522}
+
+Fixes the build with system ICU 79.1 (Unicode 18), where
+gen-regexp-special-case aborts with "Check failed: ch <= 0xffff".
+
+This is the V8 change adapted to the RegExpCaseFolding layout of the
+V8 13.6 bundled with Node.js 24; the test changes are dropped.
+
+Upstream-Status: Backport [https://github.com/v8/v8/commit/f607706154eabc4a949628a88b38dbe95cd2274c]
+Signed-off-by: Khem Raj <khem.raj@oss.qualcomm.com>
+---
+ deps/v8/src/regexp/gen-regexp-special-case.cc | 18 ++++++++++
+ deps/v8/src/regexp/regexp-parser.cc           | 18 +++++++---
+ deps/v8/src/regexp/special-case.h             | 47 ++++++++++++++++++++++++++-
+ 3 files changed, 77 insertions(+), 6 deletions(-)
+
+diff --git a/deps/v8/src/regexp/gen-regexp-special-case.cc b/deps/v8/src/regexp/gen-regexp-special-case.cc
+index 86f6b212c93..98f70975be1 100644
+--- a/deps/v8/src/regexp/gen-regexp-special-case.cc
+++ b/deps/v8/src/regexp/gen-regexp-special-case.cc
+@@ -9,6 +9,7 @@
+ 
+ #include "src/base/strings.h"
+ #include "src/regexp/special-case.h"
+#include "unicode/uchar.h"
+ 
+ namespace v8 {
+ namespace internal {
+@@ -17,6 +18,19 @@ static const base::uc32 kSurrogateStart = 0xd800;
+ static const base::uc32 kSurrogateEnd = 0xdfff;
+ static const base::uc32 kNonBmpStart = 0x10000;
+ 
+// Removes supplementary code points from |set| and returns whether any were
+// present. Since Unicode 18, the case closure of a BMP character can contain
+// supplementary code points (U+1DF95 LATIN SMALL LIGATURE LONG S WITH
+// DESCENDER S case-folds to U+00DF LATIN SMALL LETTER SHARP S). Non-unicode
+// ignoreCase matching compares UTF-16 code units, so a supplementary code
+// point never matches a BMP character and does not take part in Canonicalize.
+bool RemoveSupplementary(icu::UnicodeSet& set) {
+  constexpr UChar32 kFirstSupplementary = static_cast<UChar32>(kNonBmpStart);
+  if (!set.containsSome(kFirstSupplementary, UCHAR_MAX_VALUE)) return false;
+  set.remove(kFirstSupplementary, UCHAR_MAX_VALUE);
+  return true;
+}
+
+ // The following code generates "src/regexp/special-case.cc".
+ void PrintSet(std::ofstream& out, const char* name,
+               const icu::UnicodeSet& set) {
+@@ -51,6 +65,7 @@ void PrintSpecial(std::ofstream& out) {
+   icu::UnicodeSet current;
+   icu::UnicodeSet special_add;
+   icu::UnicodeSet ignore;
+  icu::UnicodeSet supplementary_equivalents;
+   UErrorCode status = U_ZERO_ERROR;
+   icu::UnicodeSet upper("[\\p{Lu}]", status);
+   CHECK(U_SUCCESS(status));
+@@ -63,6 +78,7 @@ void PrintSpecial(std::ofstream& out) {
+     }
+     current.set(i, i);
+     current.closeOver(USET_CASE_INSENSITIVE);
+    if (RemoveSupplementary(current)) supplementary_equivalents.add(i);
+ 
+     // Check to see if all characters in the case-folding equivalence
+     // class as defined by UnicodeSet::closeOver all map to the same
+@@ -112,6 +128,7 @@ void PrintSpecial(std::ofstream& out) {
+       UChar32 canonical = RegExpCaseFolding::Canonicalize(c);
+       current.set(c, c);
+       current.closeOver(USET_CASE_INSENSITIVE);
+      RemoveSupplementary(current);
+       current.removeAll(ignore);
+       for (int32_t j = 0; j < current.getRangeCount(); j++) {
+         for (UChar32 c2 = current.getRangeStart(j);
+@@ -124,6 +141,7 @@ void PrintSpecial(std::ofstream& out) {
+ 
+   PrintSet(out, "IgnoreSet", ignore);
+   PrintSet(out, "SpecialAddSet", special_add);
+  PrintSet(out, "SupplementaryEquivalentsSet", supplementary_equivalents);
+ }
+ 
+ void WriteHeader(const char* header_filename) {
+diff --git a/deps/v8/src/regexp/regexp-parser.cc b/deps/v8/src/regexp/regexp-parser.cc
+index 2792cd0f1e9..dd883c3eddc 100644
+--- a/deps/v8/src/regexp/regexp-parser.cc
+++ b/deps/v8/src/regexp/regexp-parser.cc
+@@ -10,6 +10,7 @@
+ #include "src/regexp/regexp-ast.h"
+ #include "src/regexp/regexp-macro-assembler.h"
+ #include "src/regexp/regexp.h"
+#include "src/regexp/special-case.h"
+ #include "src/strings/char-predicates-inl.h"
+ #include "src/utils/ostreams.h"
+ #include "src/utils/utils.h"
+@@ -156,6 +157,10 @@ void RegExpTextBuilder::FlushText() {
+ 
+ void RegExpTextBuilder::AddCharacter(base::uc16 c) {
+   FlushPendingSurrogate();
+  if (NeedsDesugaringForIgnoreCase(c)) {
+    AddClassRangesForDesugaring(c);
+    return;
+  }
+   if (characters_ == nullptr) {
+     characters_ = zone()->New<ZoneList<base::uc16>>(4, zone());
+   }
+@@ -238,15 +243,18 @@ bool RegExpTextBuilder::NeedsDesugaringForUnicode(RegExpClassRanges* cc) {
+   return false;
+ }
+ 
+-// We only use this for characters made of surrogate pairs.  All other
+-// characters outside of character classes are made case independent in the
+-// code generation.
+// Desugar supplementary characters with case equivalents and BMP characters
+// with supplementary equivalents. Other atoms are folded during code
+// generation.
+ bool RegExpTextBuilder::NeedsDesugaringForIgnoreCase(base::uc32 c) {
+ #ifdef V8_INTL_SUPPORT
+   if (IsUnicodeMode() && ignore_case()) {
+    if (c <= unibrow::Utf16::kMaxNonSurrogateCharCode) {
+      return RegExpCaseFolding::HasSupplementaryEquivalents(
+          static_cast<base::uc16>(c));
+    }
+     icu::UnicodeSet set(c, c);
+-    set.closeOver(USET_CASE_INSENSITIVE);
+-    set.removeAllStrings();
+    RegExpCaseFolding::CloseOver(set, RegExpCaseFolding::Mode::kUnicode);
+     return set.size() > 1;
+   }
+   // In the case where ICU is not included, we act as if the unicode flag is
+diff --git a/deps/v8/src/regexp/special-case.h b/deps/v8/src/regexp/special-case.h
+index 753c9231ede..80b88a308cc 100644
+--- a/deps/v8/src/regexp/special-case.h
+++ b/deps/v8/src/regexp/special-case.h
+@@ -7,8 +7,8 @@
+ 
+ #ifdef V8_INTL_SUPPORT
+ #include "src/base/logging.h"
+#include "src/base/strings.h"
+ #include "src/common/globals.h"
+-
+ #include "unicode/uchar.h"
+ #include "unicode/uniset.h"
+ #include "unicode/unistr.h"
+@@ -71,9 +71,17 @@ namespace internal {
+ // another character. Characters that match no other characters in
+ // their equivalence class are added to IgnoreSet. Characters that
+ // match at least one other character are added to SpecialAddSet.
+// Supplementary code points are ignored throughout: non-unicode matching
+// compares UTF-16 code units, so they can never match a BMP character.
+//
+// The generator additionally emits SupplementaryEquivalentsSet, the BMP
+// characters whose Unicode case closure contains supplementary code points.
+// This set is used for unicode-mode matching, see HasSupplementaryEquivalents.
+ 
+ class RegExpCaseFolding final : public AllStatic {
+  public:
+  enum class Mode { kNonUnicode, kUnicode };
+
+   static const icu::UnicodeSet& IgnoreSet();
+   static const icu::UnicodeSet& SpecialAddSet();
+ 
+@@ -108,6 +116,43 @@ class RegExpCaseFolding final : public AllStatic {
+     // h. Return cu.
+     return cu;
+   }
+
+  // Close a set of characters under case equivalence, preserving its
+  // original members. Non-unicode inputs must be UTF-16 code units.
+  static void CloseOver(icu::UnicodeSet& set, Mode mode) {
+    if (mode == Mode::kUnicode) {
+      set.closeOver(USET_SIMPLE_CASE_INSENSITIVE);
+      return;
+    }
+    DCHECK(!set.containsSome(0x10000, 0x10ffff));
+    if (IgnoreSet().containsNone(set)) {
+      CloseOverNonUnicode(set);
+      return;
+    }
+    if (IgnoreSet().containsAll(set)) return;
+    // Ignored characters neither contribute nor acquire equivalents, but
+    // must remain in the result if they were explicitly present.
+    icu::UnicodeSet ignored(set);
+    ignored.retainAll(IgnoreSet());
+    set.removeAll(IgnoreSet());
+    CloseOverNonUnicode(set);
+    set.addAll(ignored);
+  }
+
+  // Whether c has supplementary Unicode case equivalents.
+  static bool HasSupplementaryEquivalents(base::uc16 c) {
+    return SupplementaryEquivalentsSet().contains(c);
+  }
+
+ private:
+  static const icu::UnicodeSet& SupplementaryEquivalentsSet();
+
+  // Requires a set containing no IgnoreSet characters.
+  static void CloseOverNonUnicode(icu::UnicodeSet& set) {
+    set.closeOver(USET_SIMPLE_CASE_INSENSITIVE);
+    set.removeAll(IgnoreSet());
+    set.remove(0x10000, 0x10ffff);
+  }
+ };
+ 
+ }  // namespace internal
@@ -30,6 +30,7 @@ SRC_URI = "https://nodejs.org/dist/v${PV}/node-v${PV}.tar.xz \
           file://0007-positional-args.patch \
           file://0008-custom-env.patch \
           file://0010-v8-fix-Wtemplate-body-error-with-GCC-15-on-ia32.patch \
+           file://0011-v8-handle-supplementary-case-equivalents-of-BMP-characters.patch \
           file://run-ptest \
           "
 SRC_URI:append:class-target = " \