Remove GTEST_USES_PCRE references

Nothing defines GTEST_USES_PCRE anymore. It was only meant for
internal use, so nothing public should be relying on it:
https://github.com/google/googletest/issues/2735#issuecomment-644849438.

Found when compiling with "-Wundef".

Fixes #2735.

PiperOrigin-RevId: 507823660
Change-Id: Ie19e576ff01dc3b16381338578ece92adccfc09b

googlemock/test/gmock-spec-builders_test.cc

@@ -1088,16 +1088,7 @@ TEST(UnexpectedCallTest, UnsatisfiedPrerequisites) {
 
   // Verifies that the failure message contains the two unsatisfied
   // pre-requisites but not the satisfied one.
-#if GTEST_USES_PCRE
-  EXPECT_THAT(
-      r.message(),
-      ContainsRegex(
-          // PCRE has trouble using (.|\n) to match any character, but
-          // supports the (?s) prefix for using . to match any character.
-          "(?s)the following immediate pre-requisites are not satisfied:\n"
-          ".*: pre-requisite #0\n"
-          ".*: pre-requisite #1"));
-#elif GTEST_USES_POSIX_RE
+#if GTEST_USES_POSIX_RE
   EXPECT_THAT(r.message(),
               ContainsRegex(
                   // POSIX RE doesn't understand the (?s) prefix, but has no
@@ -1112,7 +1103,7 @@ TEST(UnexpectedCallTest, UnsatisfiedPrerequisites) {
                   "the following immediate pre-requisites are not satisfied:"));
   EXPECT_THAT(r.message(), ContainsRegex(": pre-requisite #0"));
   EXPECT_THAT(r.message(), ContainsRegex(": pre-requisite #1"));
-#endif  // GTEST_USES_PCRE
+#endif  // GTEST_USES_POSIX_RE
 
   b.DoB(1);
   b.DoB(3);

googletest/test/googletest-death-test-test.cc

@@ -327,23 +327,6 @@ TEST_F(TestForDeathTest, SingleStatement) {
 #pragma GCC diagnostic pop
 #endif
 
-#if GTEST_USES_PCRE
-
-void DieWithEmbeddedNul() {
-  fprintf(stderr, "Hello%cmy null world.\n", '\0');
-  fflush(stderr);
-  _exit(1);
-}
-
-// Tests that EXPECT_DEATH and ASSERT_DEATH work when the error
-// message has a NUL character in it.
-TEST_F(TestForDeathTest, EmbeddedNulInMessage) {
-  EXPECT_DEATH(DieWithEmbeddedNul(), "my null world");
-  ASSERT_DEATH(DieWithEmbeddedNul(), "my null world");
-}
-
-#endif  // GTEST_USES_PCRE
-
 // Tests that death test macros expand to code which interacts well with switch
 // statements.
 TEST_F(TestForDeathTest, SwitchStatement) {
@@ -521,16 +504,12 @@ TEST_F(TestForDeathTest, AcceptsAnythingConvertibleToRE) {
   const testing::internal::RE regex(regex_c_str);
   EXPECT_DEATH(GlobalFunction(), regex);
 
-#if !GTEST_USES_PCRE
-
   const ::std::string regex_std_str(regex_c_str);
   EXPECT_DEATH(GlobalFunction(), regex_std_str);
 
   // This one is tricky; a temporary pointer into another temporary.  Reference
   // lifetime extension of the pointer is not sufficient.
   EXPECT_DEATH(GlobalFunction(), ::std::string(regex_c_str).c_str());
-
-#endif  // !GTEST_USES_PCRE
 }
 
 // Tests that a non-void function can be used in a death test.