explicit_seed_seq_test: work around/disable bogus warnings in GCC 12

PiperOrigin-RevId: 455129922
Change-Id: I3b2a62cbf50057b3ea9b73c2edb44271dc46986c

absl/random/internal/explicit_seed_seq_test.cc

@@ -140,10 +140,8 @@ TEST(ExplicitSeedSeq, CopyAndMoveConstructors) {
     ExplicitSeedSeq seq_copy(seq_from_entropy);
     EXPECT_EQ(seq_copy.size(), seq_from_entropy.size());
 
-    std::vector<uint32_t> seeds_1;
+    std::vector<uint32_t> seeds_1(1000, 0);
-    seeds_1.resize(1000, 0);
+    std::vector<uint32_t> seeds_2(1000, 1);
-    std::vector<uint32_t> seeds_2;
-    seeds_2.resize(1000, 1);
 
     seq_from_entropy.generate(seeds_1.begin(), seeds_1.end());
     seq_copy.generate(seeds_2.begin(), seeds_2.end());
@@ -157,10 +155,8 @@ TEST(ExplicitSeedSeq, CopyAndMoveConstructors) {
     }
     ExplicitSeedSeq another_seq(std::begin(entropy), std::end(entropy));
 
-    std::vector<uint32_t> seeds_1;
+    std::vector<uint32_t> seeds_1(1000, 0);
-    seeds_1.resize(1000, 0);
+    std::vector<uint32_t> seeds_2(1000, 0);
-    std::vector<uint32_t> seeds_2;
-    seeds_2.resize(1000, 0);
 
     seq_from_entropy.generate(seeds_1.begin(), seeds_1.end());
     another_seq.generate(seeds_2.begin(), seeds_2.end());
@@ -169,7 +165,15 @@ TEST(ExplicitSeedSeq, CopyAndMoveConstructors) {
     EXPECT_THAT(seeds_1, Not(Pointwise(Eq(), seeds_2)));
 
     // Apply the assignment-operator.
+    // GCC 12 has a false-positive -Wstringop-overflow warning here.
+#if ABSL_INTERNAL_HAVE_MIN_GNUC_VERSION(12, 0)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wstringop-overflow"
+#endif
     another_seq = seq_from_entropy;
+#if ABSL_INTERNAL_HAVE_MIN_GNUC_VERSION(12, 0)
+#pragma GCC diagnostic pop
+#endif
 
     // Re-generate seeds.
     seq_from_entropy.generate(seeds_1.begin(), seeds_1.end());
@@ -181,15 +185,13 @@ TEST(ExplicitSeedSeq, CopyAndMoveConstructors) {
   // Move constructor.
   {
     // Get seeds from seed-sequence constructed from entropy.
-    std::vector<uint32_t> seeds_1;
+    std::vector<uint32_t> seeds_1(1000, 0);
-    seeds_1.resize(1000, 0);
     seq_from_entropy.generate(seeds_1.begin(), seeds_1.end());
 
     // Apply move-constructor move the sequence to another instance.
     absl::random_internal::ExplicitSeedSeq moved_seq(
         std::move(seq_from_entropy));
-    std::vector<uint32_t> seeds_2;
+    std::vector<uint32_t> seeds_2(1000, 1);
-    seeds_2.resize(1000, 1);
     moved_seq.generate(seeds_2.begin(), seeds_2.end());
     // Verify that seeds produced by moved-instance are the same as original.
     EXPECT_THAT(seeds_1, Pointwise(Eq(), seeds_2));