re2: revert "churn to new Abseil"

The new Abseil is not available in vcpkg, so it fails RE2 CI.
Roll back to the older version for now.

This reverts commit 7df5539.

Author: rsc

CMakeLists.txt

@@ -87,7 +87,7 @@ set(ABSL_DEPS
 # indirectly), let that take precedence over any copy of Abseil that might have
 # been installed on the system. And likewise for ICU, GoogleTest and Benchmark.
 if(NOT TARGET absl::base)
-  find_package(absl 20250814 REQUIRED)
+  find_package(absl REQUIRED)
 endif()
 list(APPEND REQUIRES ${ABSL_DEPS})
 

MODULE.bazel

@@ -12,8 +12,8 @@ module(
 
 bazel_dep(name = "platforms", version = "1.0.0")
 bazel_dep(name = "apple_support", version = "1.22.1")
-bazel_dep(name = "rules_cc", version = "0.2.0")
-bazel_dep(name = "abseil-cpp", version = "20250814.1")
+bazel_dep(name = "rules_cc", version = "0.1.4")
+bazel_dep(name = "abseil-cpp", version = "20250512.1")
 bazel_dep(name = "rules_python", version = "1.5.1")
 bazel_dep(name = "pybind11_bazel", version = "2.13.6")
 

re2/dfa.cc

@@ -1015,7 +1015,7 @@ void DFA::RunWorkqOnByte(Workq* oldq, Workq* newq,
 DFA::State* DFA::RunStateOnByteUnlocked(State* state, int c) {
   // Keep only one RunStateOnByte going
   // even if the DFA is being run by multiple threads.
-  absl::MutexLock l(mutex_);
+  absl::MutexLock l(&mutex_);
   return RunStateOnByte(state, c);
 }
 
@@ -1267,7 +1267,7 @@ DFA::StateSaver::~StateSaver() {
 DFA::State* DFA::StateSaver::Restore() {
   if (is_special_)
     return special_;
-  absl::MutexLock l(dfa_->mutex_);
+  absl::MutexLock l(&dfa_->mutex_);
   State* s = dfa_->CachedState(inst_, ninst_, flag_);
   if (s == NULL)
     ABSL_LOG(DFATAL) << "StateSaver failed to restore state.";
@@ -1730,7 +1730,7 @@ bool DFA::AnalyzeSearchHelper(SearchParams* params, StartInfo* info,
   if (start != NULL)
     return true;
 
-  absl::MutexLock l(mutex_);
+  absl::MutexLock l(&mutex_);
   start = info->start.load(std::memory_order_relaxed);
   if (start != NULL)
     return true;
@@ -2050,7 +2050,7 @@ bool DFA::PossibleMatchRange(std::string* min, std::string* max, int maxlen) {
   // Build minimum prefix.
   State* s = params.start;
   min->clear();
-  absl::MutexLock lock(mutex_);
+  absl::MutexLock lock(&mutex_);
   for (int i = 0; i < maxlen; i++) {
     if (previously_visited_states[s] > kMaxEltRepetitions)
       break;

re2/regexp.cc

@@ -95,7 +95,7 @@ int Regexp::Ref() {
   if (ref_ < kMaxRef)
     return ref_;
 
-  absl::MutexLock l(*ref_mutex());
+  absl::MutexLock l(ref_mutex());
   return (*ref_map())[this];
 }
 
@@ -108,7 +108,7 @@ Regexp* Regexp::Incref() {
     });
 
     // Store ref count in overflow map.
-    absl::MutexLock l(*ref_mutex());
+    absl::MutexLock l(ref_mutex());
     if (ref_ == kMaxRef) {
       // already overflowed
       (*ref_map())[this]++;
@@ -128,7 +128,7 @@ Regexp* Regexp::Incref() {
 void Regexp::Decref() {
   if (ref_ == kMaxRef) {
     // Ref count is stored in overflow map.
-    absl::MutexLock l(*ref_mutex());
+    absl::MutexLock l(ref_mutex());
     int r = (*ref_map())[this] - 1;
     if (r < kMaxRef) {
       ref_ = static_cast<uint16_t>(r);

re2/testing/regexp_benchmark.cc

@@ -964,7 +964,7 @@ void SearchRE2(benchmark::State& state, const char* regexp,
 
 Prog* GetCachedProg(const char* regexp) {
   static auto& mutex = *new absl::Mutex;
-  absl::MutexLock lock(mutex);
+  absl::MutexLock lock(&mutex);
   static auto& cache = *new absl::flat_hash_map<std::string, Prog*>;
   Prog* prog = cache[regexp];
   if (prog == NULL) {
@@ -982,7 +982,7 @@ Prog* GetCachedProg(const char* regexp) {
 
 PCRE* GetCachedPCRE(const char* regexp) {
   static auto& mutex = *new absl::Mutex;
-  absl::MutexLock lock(mutex);
+  absl::MutexLock lock(&mutex);
   static auto& cache = *new absl::flat_hash_map<std::string, PCRE*>;
   PCRE* re = cache[regexp];
   if (re == NULL) {
@@ -995,7 +995,7 @@ PCRE* GetCachedPCRE(const char* regexp) {
 
 RE2* GetCachedRE2(const char* regexp) {
   static auto& mutex = *new absl::Mutex;
-  absl::MutexLock lock(mutex);
+  absl::MutexLock lock(&mutex);
   static auto& cache = *new absl::flat_hash_map<std::string, RE2*>;
   RE2* re = cache[regexp];
   if (re == NULL) {