[scudo] Test ScudoReleaseTest.BufferPool with a buffer pool allocated on the heap

[fabio-d]

Summary

The previous code resulted in 252 KiB being allocated on the stack,
which caused a stack overflow on Fuchsia.

[fabio-d]

As discussed offline with @Chia-hungDuan, moved the buffer pool to the heap instead of simply allocating less on the stack.

[Chia-hungDuan]

LGTM

compiler-rt/lib/scudo/standalone/tests/release_test.cpp

570

Can we have some comment here to say why we have to allocate the buffer on heap?

[fabio-d]

compiler-rt/lib/scudo/standalone/tests/release_test.cpp

570

Done, thanks!

compiler-rt/lib/scudo/standalone/tests/release_test.cpp

TEST(ScudoReleaseTest, ReleasePartialRegion) {
   testReleasePartialRegion<scudo::AndroidSizeClassMap>();
   testReleasePartialRegion<scudo::FuchsiaSizeClassMap>();
   testReleasePartialRegion<scudo::SvelteSizeClassMap>();
 }
 
 TEST(ScudoReleaseTest, BufferPool) {
   constexpr scudo::uptr StaticBufferCount = SCUDO_WORDSIZE - 1;
   constexpr scudo::uptr StaticBufferSize = 512U;
-  scudo::BufferPool<StaticBufferCount, StaticBufferSize> Pool;
+  using BufferPool = scudo::BufferPool<StaticBufferCount, StaticBufferSize>;
+  std::unique_ptr<BufferPool> Pool(new BufferPool());
 
   std::vector<std::pair<scudo::uptr *, scudo::uptr>> Buffers;
   for (scudo::uptr I = 0; I < StaticBufferCount; ++I) {
-    scudo::uptr *P = Pool.getBuffer(StaticBufferSize);
-    EXPECT_TRUE(Pool.isStaticBufferTestOnly(P, StaticBufferSize));
+    scudo::uptr *P = Pool->getBuffer(StaticBufferSize);
+    EXPECT_TRUE(Pool->isStaticBufferTestOnly(P, StaticBufferSize));
     Buffers.emplace_back(P, StaticBufferSize);
   }
 
   // The static buffer is supposed to be used up.
-  scudo::uptr *P = Pool.getBuffer(StaticBufferSize);
-  EXPECT_FALSE(Pool.isStaticBufferTestOnly(P, StaticBufferSize));
+  scudo::uptr *P = Pool->getBuffer(StaticBufferSize);
+  EXPECT_FALSE(Pool->isStaticBufferTestOnly(P, StaticBufferSize));
 
-  Pool.releaseBuffer(P, StaticBufferSize);
+  Pool->releaseBuffer(P, StaticBufferSize);
   for (auto &Buffer : Buffers)
-    Pool.releaseBuffer(Buffer.first, Buffer.second);
+    Pool->releaseBuffer(Buffer.first, Buffer.second);
 }