PARQUET-513: Fail build if valgrind finds error during ctest, fix a c…

…ore dump

Also adds an option to use ccache with a custom gcc toolchain.

Fixes an improper memory access stemming from a unit test that had a wrong parameter.

Author: Wes McKinney <wes@cloudera.com>

Closes apache#42 from wesm/PARQUET-513 and squashes the following commits:

43df9e7 [Wes McKinney] Fix core dump from unit test bug
b46c617 [Wes McKinney] Fail build if valgrind finds error during ctest

Change-Id: I4e04fee7db2ed7a0af21ab25b9d7566314d07ac4

cpp/src/parquet/schema/schema-converter-test.cc

@@ -125,7 +125,7 @@ TEST_F(TestSchemaConverter, NotEnoughChildren) {
  SchemaElement elt;
  std::vector<SchemaElement> elements;
  elements.push_back(NewGroup(name_, FieldRepetitionType::REPEATED, 2));
- ASSERT_THROW(Convert(&elements[0], 2), ParquetException);
+ ASSERT_THROW(Convert(&elements[0], 1), ParquetException);
 }
 
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