Add build configurations for Linux and Windows

Move some build flags to the build configuration (bazelrc).
Enable more warnings and treat them as errors.

Author: werat

.bazelrc

@@ -1,20 +1,31 @@
 # Try loading per-user configuration.
 try-import %workspace%/user.bazelrc
 
+# Linux-specific configuration.
+build:linux --cxxopt=-std=c++17
+build:linux --copt=-Wall
+build:linux --copt=-Wextra
+build:linux --copt=-Wpedantic
+build:linux --copt=-Werror
+
+# Windows-specific configuration.
+build:windows --cxxopt=/std:c++17
+build:windows --copt=/W4
+build:windows --copt=/WX
+
 # On Windows clang.exe tries to find the MSVC toolchain by looking at environmental variables,
 # querying Visual Studio instances via COM (>=2017) and reading Registry keys (<=2015).
 # ProgramData data is typically required for COM api querying, unless a custom location for
 # Visual Studio package cache is defined.
-
-build --action_env=ProgramData
+build:windows --action_env=ProgramData
 
 # AddressSanitizer (ASan).
 build:asan --strip=never
-build:asan --copt -fsanitize=address
-build:asan --copt -DADDRESS_SANITIZER
-build:asan --copt -O0
-build:asan --copt -g
-build:asan --copt -fno-omit-frame-pointer
+build:asan --copt=-fsanitize=address
+build:asan --copt=-DADDRESS_SANITIZER
+build:asan --copt=-O0
+build:asan --copt=-g
+build:asan --copt=-fno-omit-frame-pointer
 build:asan --linkopt -fsanitize=address
 
 # MemorySanitizer (MSan).

.github/workflows/main.yml

@@ -25,6 +25,10 @@ jobs:
           sudo ./llvm.sh ${{ matrix.tag }}
           sudo apt install -y llvm-${{ matrix.tag }}-dev libclang-${{ matrix.tag }}-dev liblldb-${{ matrix.tag }}-dev
 
+      - name: Setup Bazel
+        run: |
+          echo "build --config=linux" > user.bazelrc
+
       - name: Build
         run: bazel build :all
 

BUILD

@@ -21,7 +21,6 @@ COPTS = select({
         "/external:I external/llvm_project/include",
     ],
     "//conditions:default": [
-        "-std=c++17",
         "-fno-exceptions",
         "-fno-rtti",
     ],

README.md

@@ -87,20 +87,35 @@ Now you can build and test `lldb-eval`:
 
 ```bash
 # Build and run all tests
-bazel test :all
+bazel test --config=linux :all
 
 # Evaluate a sample expression
-bazel run :main -- "(1 + 2) * 42 / 4"
+bazel run --config=windows :main -- "(1 + 2) * 42 / 4"
 ```
 
-Depending on your distribution of LLVM, you may need to provide
+> **Hint:** You can add this option to your `user.bazelrc` !
+
+Depending on your distribution of LLVM, you may also need to provide
 `--@llvm_project//:llvm_build={static,dynamic}` flag. For example, if your
 `liblldb.so` is linked dynamically (this is the case when installing via `apt`),
 then you need to use `llvm_build=dynamic`. The build script [tries to choose the
 correct default value automatically](/build_defs/repo_rules.bzl#L21), but it can
 be wrong in some situations (please, report and contribute 🙂).
 
-> **Hint:** You can add this option to your `user.bazelrc`
+> **Hint:** You can add this option to your `user.bazelrc` !
+
+### Local per-repo Bazel config
+
+You can create `user.bazelrc` in the repository root and put there your local
+configuration. Check [Bazel docs](https://docs.bazel.build/versions/master/guide.html#bazelrc)
+for the format. For example:
+
+```bash
+# Building on Linux
+build --config=linux
+# Using statically linked liblldb.so
+build ----@llvm_project//:llvm_build=static
+```
 
 ## Disclamer
 

src/eval.cc

@@ -43,7 +43,7 @@ void EvalError::Set(EvalErrorCode code, const std::string& message) {
 void EvalError::Clear() { *this = {}; }
 
 EvalErrorCode EvalError::code() const { return code_; }
-const std::string& EvalError::message() const { return message_; };
+const std::string& EvalError::message() const { return message_; }
 
 EvalError::operator bool() const { return code_ != EvalErrorCode::OK; }
 

src/runner.cc

@@ -47,6 +47,8 @@ void SetupLLDBServerEnv(const Runfiles& runfiles) {
 #ifndef _WIN32
   std::string lldb_server = runfiles.Rlocation("llvm_project/bin/lldb-server");
   setenv("LLDB_DEBUGSERVER_PATH", lldb_server.c_str(), 0);
+#else
+  (void)runfiles;
 #endif  // !_WIN32
 }
 

src/value.cc

@@ -149,6 +149,7 @@ lldb::SBValue Value::AsSbValue(lldb::SBTarget target) const {
                                lldb::eBasicTypeDouble);
         }
       }
+      unreachable("Scalar::Type wasn't exhausted in the switch statement.");
     }
     case Type::POINTER: {
       return CreateSbValue(target, pointer_.addr(), pointer_.type());

tools/BUILD

@@ -8,7 +8,6 @@ COPTS = select({
         "/external:I external/llvm_project/include",
     ],
     "//conditions:default": [
-        "-std=c++17",
         "-fno-exceptions",
         "-fno-rtti",
     ],

tools/fuzzer/expr_gen.cc

@@ -30,11 +30,11 @@ struct ExprKindInfo {
 };
 
 static const std::array<ExprKindInfo, NUM_EXPR_KINDS> EXPR_KIND_INFO = {{
-    {1.0, 0.0},  // ExprKind::IntegerConstant
-    {0.0, 0.0},  // ExprKind::DoubleConstant
-    {1.0, 0.0},  // ExprKind::VariableExpr
-    {7.0, 0.4},  // ExprKind::BinaryExpr
-    {3.0, 0.4},  // ExprKind::UnaryExpr
+    {1.0f, 0.0f},  // ExprKind::IntegerConstant
+    {0.0f, 0.0f},  // ExprKind::DoubleConstant
+    {1.0f, 0.0f},  // ExprKind::VariableExpr
+    {7.0f, 0.4f},  // ExprKind::BinaryExpr
+    {3.0f, 0.4f},  // ExprKind::UnaryExpr
 }};
 
 bool ExprGenerator::fifty_fifty() {
@@ -136,6 +136,7 @@ Expr ExprGenerator::gen_with_weights(const WeightsArray& weights) {
 
     default:
       assert(false && "Unreachable");
+      exit(1);
   }
 }
 

tools/lexer.cc

@@ -32,6 +32,8 @@
 #include "llvm/Support/Host.h"
 
 int main(int argc, char** argv) {
+  (void)argc;
+
   // "parse" command line arguments.
   std::string expr = argv[1];