[IMPALA-6084] Avoid "using namespace llvm" in C++ source files

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: Impala 2.11.0
• Component/s: Backend
• Labels: newbie
• Target Version: Product Backlog
• Epic Color: ghx-label-5
• Assignee: Jin Chul Kim
• Reporter: Tim Armstrong
• Created: 19/Oct/17 19:00
• Updated: 16/Nov/17 01:45
• Resolved: 16/Nov/17 01:45

Description

There are a large number of places in the backend where we import everything from the llvm namespace into the global namespace. There's a lot of things in the llvm namespace, and it changes from version-to-version (e.g. they have llvm::make_unique). Instead of importing everything we should either import them selectively (e.g. using llvm::Function or just use the llvm:: prefix.

$ git grep 'using namespace lvm'
be/src/benchmarks/hash-benchmark.cc:using namespace llvm;
be/src/codegen/codegen-anyval.cc:using namespace llvm;
be/src/codegen/codegen-callgraph.cc:using namespace llvm;
be/src/codegen/codegen-symbol-emitter.cc:using namespace llvm;
be/src/codegen/codegen-symbol-emitter.cc:using namespace llvm::object;
be/src/codegen/codegen-util.cc:using namespace llvm;
be/src/codegen/instruction-counter-test.cc:using namespace llvm;
be/src/codegen/instruction-counter.cc:using namespace llvm;
be/src/codegen/llvm-codegen-test.cc:using namespace llvm;
be/src/codegen/llvm-codegen.cc:using namespace llvm;
be/src/exec/blocking-join-node.cc:using namespace llvm;
be/src/exec/exec-node.cc:using namespace llvm;
be/src/exec/filter-context.cc:using namespace llvm;
be/src/exec/hdfs-avro-scanner.cc:using namespace llvm;
be/src/exec/hdfs-parquet-scanner.cc:using namespace llvm;
be/src/exec/hdfs-scan-node-base.cc:using namespace llvm;
be/src/exec/hdfs-scanner.cc:using namespace llvm;
be/src/exec/hdfs-sequence-scanner.cc:using namespace llvm;
be/src/exec/hdfs-text-scanner.cc:using namespace llvm;
be/src/exec/partitioned-aggregation-node.cc:using namespace llvm;
be/src/exec/text-converter.cc:using namespace llvm;
be/src/exec/topn-node.cc:using namespace llvm;
be/src/exec/union-node.cc:using namespace llvm;
be/src/exprs/agg-fn-evaluator.cc:using namespace llvm;
be/src/exprs/agg-fn.cc:using namespace llvm;
be/src/exprs/case-expr.cc:using namespace llvm;
be/src/exprs/compound-predicates.cc:using namespace llvm;
be/src/exprs/expr-codegen-test.cc:using namespace llvm;
be/src/exprs/expr-test.cc:using namespace llvm;
be/src/exprs/literal.cc:using namespace llvm;
be/src/exprs/null-literal.cc:using namespace llvm;
be/src/exprs/scalar-expr.cc:using namespace llvm;
be/src/exprs/slot-ref.cc:using namespace llvm;
be/src/runtime/runtime-state.cc:using namespace llvm;
be/src/runtime/tuple.cc:using namespace llvm;
be/src/runtime/types.cc:using namespace llvm;
be/src/util/tuple-row-compare.cc:using namespace llvm;