From bd2a910a63f298aa38fac282f1ed858c21075eeb Mon Sep 17 00:00:00 2001 From: Raphael Isemann Date: Tue, 24 Sep 2019 06:58:39 +0000 Subject: [PATCH] Ignore generated @import statements in the expression evaluator Summary: The ClangModulesDeclVendor is currently interpreting all injected `@import` statements in our expression wrapper as modules that the user has explicitly requested to be persistently loaded. As we inject `@import` statements with our std module prototype, the ClangModulesDeclVendor will start compiling and loading unrelated C++ modules because it thinks the user has requested that it should load them. As the ClangModulesDeclVendor is lacking the setup to compile these modules (e.g. it lacks the include paths), it will then actually just fail to compile them and cause the whole expression evaluation to fail. This causes these tests to fail on systems that enable the ClangModulesDeclVendor (such as macOS). This patch fixes this by preventing the ClangModulesDeclVendor from interpreting `@import` statements in the wrapper source code. This is done by check if the import happens in the fake source file containing our wrapper code (which implies it was generated by LLDB). This patch doesn't reenable the tests as there is more work needed to get the tests running on macOS (D67760) Reviewers: aprantl, shafik, jingham Subscribers: lldb-commits Tags: #c_modules_in_lldb, #lldb Differential Revision: https://reviews.llvm.org/D61565 llvm-svn: 372690 --- .../Clang/ClangExpressionParser.cpp | 18 ++++++++++++++---- .../Clang/ClangExpressionSourceCode.cpp | 7 +++++-- .../Clang/ClangExpressionSourceCode.h | 3 +++ 3 files changed, 22 insertions(+), 6 deletions(-) diff --git a/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp b/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp index d48e6726aa64..cb0e985b8cf5 100644 --- a/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp +++ b/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp @@ -105,16 +105,26 @@ using namespace lldb_private; class ClangExpressionParser::LLDBPreprocessorCallbacks : public PPCallbacks { ClangModulesDeclVendor &m_decl_vendor; ClangPersistentVariables &m_persistent_vars; + clang::SourceManager &m_source_mgr; StreamString m_error_stream; bool m_has_errors = false; public: LLDBPreprocessorCallbacks(ClangModulesDeclVendor &decl_vendor, - ClangPersistentVariables &persistent_vars) - : m_decl_vendor(decl_vendor), m_persistent_vars(persistent_vars) {} + ClangPersistentVariables &persistent_vars, + clang::SourceManager &source_mgr) + : m_decl_vendor(decl_vendor), m_persistent_vars(persistent_vars), + m_source_mgr(source_mgr) {} void moduleImport(SourceLocation import_location, clang::ModuleIdPath path, const clang::Module * /*null*/) override { + // Ignore modules that are imported in the wrapper code as these are not + // loaded by the user. + llvm::StringRef filename = + m_source_mgr.getPresumedLoc(import_location).getFilename(); + if (filename == ClangExpressionSourceCode::g_prefix_file_name) + return; + SourceModule module; for (const std::pair &component : path) @@ -572,8 +582,8 @@ ClangExpressionParser::ClangExpressionParser(ExecutionContextScope *exe_scope, E llvm::cast( target_sp->GetPersistentExpressionStateForLanguage( lldb::eLanguageTypeC)); - std::unique_ptr pp_callbacks( - new LLDBPreprocessorCallbacks(*decl_vendor, *clang_persistent_vars)); + std::unique_ptr pp_callbacks(new LLDBPreprocessorCallbacks( + *decl_vendor, *clang_persistent_vars, m_compiler->getSourceManager())); m_pp_callbacks = static_cast(pp_callbacks.get()); m_compiler->getPreprocessor().addPPCallbacks(std::move(pp_callbacks)); diff --git a/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionSourceCode.cpp b/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionSourceCode.cpp index bf1bd5da39b5..ee890ac08e64 100644 --- a/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionSourceCode.cpp +++ b/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionSourceCode.cpp @@ -29,9 +29,12 @@ using namespace lldb_private; +#define PREFIX_NAME "" + +const llvm::StringRef ClangExpressionSourceCode::g_prefix_file_name = PREFIX_NAME; + const char *ClangExpressionSourceCode::g_expression_prefix = - R"( -#line 1 "" +"#line 1 \"" PREFIX_NAME R"(" #ifndef offsetof #define offsetof(t, d) __builtin_offsetof(t, d) #endif diff --git a/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionSourceCode.h b/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionSourceCode.h index 2f966ff07fb0..1d159670b962 100644 --- a/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionSourceCode.h +++ b/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionSourceCode.h @@ -23,6 +23,9 @@ class ExecutionContext; class ClangExpressionSourceCode : public ExpressionSourceCode { public: + /// The file name we use for the wrapper code that we inject before + /// the user expression. + static const llvm::StringRef g_prefix_file_name; static const char *g_expression_prefix; static ClangExpressionSourceCode *CreateWrapped(llvm::StringRef filename,