Clang: Improve compilation database generation

Do not use CompilerOptionsBuilder anymore because we don't
need much tweaking for projectPart data and can do it better
specifically for the generator.

Fixes: QTCREATORBUG-21936
Change-Id: I00ad872c703598a9a88af29399b428520dd5cb3b
Reviewed-by: Marco Bubke <marco.bubke@qt.io>

src/plugins/clangcodemodel/clangutils.cpp

@@ -34,12 +34,13 @@
 #include <coreplugin/idocument.h>
 #include <cpptools/baseeditordocumentparser.h>
 #include <cpptools/compileroptionsbuilder.h>
+#include <cpptools/cppcodemodelsettings.h>
 #include <cpptools/cppmodelmanager.h>
+#include <cpptools/cpptoolsreuse.h>
 #include <cpptools/editordocumenthandle.h>
 #include <cpptools/projectpart.h>
-#include <cpptools/cppcodemodelsettings.h>
-#include <cpptools/cpptoolsreuse.h>
 #include <projectexplorer/buildconfiguration.h>
+#include <projectexplorer/kitinformation.h>
 #include <projectexplorer/projectexplorerconstants.h>
 #include <projectexplorer/target.h>
 
@@ -300,6 +301,18 @@ QString diagnosticCategoryPrefixRemoved(const QString &text)
     return text;
 }
 
+static ::Utils::FileName compilerPath(const CppTools::ProjectPart &projectPart)
+{
+    ProjectExplorer::Target *target = projectPart.project->activeTarget();
+    if (!target)
+        return ::Utils::FileName();
+
+    ProjectExplorer::ToolChain *toolchain = ProjectExplorer::ToolChainKitInformation::toolChain(
+        target->kit(), ProjectExplorer::Constants::CXX_LANGUAGE_ID);
+
+    return toolchain->compilerCommand();
+}
+
 static ::Utils::FileName buildDirectory(const CppTools::ProjectPart &projectPart)
 {
     ProjectExplorer::Target *target = projectPart.project->activeTarget();
@@ -313,17 +326,60 @@ static ::Utils::FileName buildDirectory(const CppTools::ProjectPart &projectPart
     return buildConfig->buildDirectory();
 }
 
-static QJsonObject createFileObject(CompilerOptionsBuilder &optionsBuilder,
-                                    const ProjectFile &projFile,
-                                    const ::Utils::FileName &buildDir)
+static QStringList projectPartArguments(const ProjectPart &projectPart)
 {
-    const ProjectFile::Kind kind = ProjectFile::classify(projFile.path);
-    optionsBuilder.updateFileLanguage(kind);
+    QStringList args;
+    args << compilerPath(projectPart).toString();
+    args << "-c";
+    if (projectPart.toolchainType != ProjectExplorer::Constants::MSVC_TOOLCHAIN_TYPEID) {
+        args << "--target=" + projectPart.toolChainTargetTriple;
+        args << (projectPart.toolChainWordWidth == ProjectPart::WordWidth64Bit
+                     ? QLatin1String("-m64")
+                     : QLatin1String("-m32"));
+    }
+    args << projectPart.compilerFlags;
+    for (const ProjectExplorer::HeaderPath &headerPath : projectPart.headerPaths) {
+        if (headerPath.type == ProjectExplorer::HeaderPathType::User) {
+            args << "-I" + headerPath.path;
+        } else if (headerPath.type == ProjectExplorer::HeaderPathType::System) {
+            args << (projectPart.toolchainType == ProjectExplorer::Constants::MSVC_TOOLCHAIN_TYPEID
+                         ? "-I"
+                         : "-isystem")
+                        + headerPath.path;
+        }
+    }
+    for (const ProjectExplorer::Macro &macro : projectPart.projectMacros) {
+        args.append(QString::fromUtf8(
+            macro.toKeyValue(macro.type == ProjectExplorer::MacroType::Define ? "-D" : "-U")));
+    }
 
+    return args;
+}
+
+static QJsonObject createFileObject(const ::Utils::FileName &buildDir,
+                                    const QStringList &arguments,
+                                    const ProjectPart &projectPart,
+                                    const ProjectFile &projFile)
+{
     QJsonObject fileObject;
     fileObject["file"] = projFile.path;
-    QJsonArray args = QJsonArray::fromStringList(optionsBuilder.options());
-    args.prepend(kind == ProjectFile::CXXSource ? "clang++" : "clang");
+    QJsonArray args = QJsonArray::fromStringList(arguments);
+
+    const ProjectFile::Kind kind = ProjectFile::classify(projFile.path);
+    if (projectPart.toolchainType == ProjectExplorer::Constants::MSVC_TOOLCHAIN_TYPEID
+        || projectPart.toolchainType == ProjectExplorer::Constants::CLANG_CL_TOOLCHAIN_TYPEID) {
+        if (ProjectFile::isC(kind))
+            args.append("/TC");
+        else if (ProjectFile::isCxx(kind))
+            args.append("/TP");
+    } else {
+        QStringList langOption
+            = createLanguageOptionGcc(kind,
+                                      projectPart.languageExtensions
+                                          & ::Utils::LanguageExtension::ObjectiveC);
+        for (const QString &langOptionPart : langOption)
+            args.append(langOptionPart);
+    }
     args.append(QDir::toNativeSeparators(projFile.path));
     fileObject["arguments"] = args;
     fileObject["directory"] = buildDir.toString();
@@ -338,17 +394,12 @@ void generateCompilationDB(::Utils::FileName projectDir, CppTools::ProjectInfo p
     if (!fileOpened)
         return;
     compileCommandsFile.write("[");
+
     for (ProjectPart::Ptr projectPart : projectInfo.projectParts()) {
         const ::Utils::FileName buildDir = buildDirectory(*projectPart);
-
-        CompilerOptionsBuilder optionsBuilder(*projectPart,
-                                              UseSystemHeader::No,
-                                              UseTweakedHeaderPaths::No);
-        optionsBuilder.build(CppTools::ProjectFile::Unclassified,
-                             CppTools::UsePrecompiledHeaders::No);
-
+        const QStringList args = projectPartArguments(*projectPart);
         for (const ProjectFile &projFile : projectPart->files) {
-            const QJsonObject json = createFileObject(optionsBuilder, projFile, buildDir);
+            const QJsonObject json = createFileObject(buildDir, args, *projectPart, projFile);
             if (compileCommandsFile.size() > 1)
                 compileCommandsFile.write(",");
             compileCommandsFile.write('\n' + QJsonDocument(json).toJson().trimmed());

src/plugins/cpptools/compileroptionsbuilder.cpp

@@ -172,7 +172,7 @@ void CompilerOptionsBuilder::addSyntaxOnly()
     isClStyle() ? add("/Zs") : add("-fsyntax-only");
 }
 
-static QStringList createLanguageOptionGcc(ProjectFile::Kind fileKind, bool objcExt)
+QStringList createLanguageOptionGcc(ProjectFile::Kind fileKind, bool objcExt)
 {
     QStringList options;
 

src/plugins/cpptools/compileroptionsbuilder.h

@@ -40,6 +40,7 @@ enum class UseBuildSystemWarnings : char { Yes, No };
 
 CPPTOOLS_EXPORT QStringList XclangArgs(const QStringList &args);
 CPPTOOLS_EXPORT QStringList clangArgsForCl(const QStringList &args);
+CPPTOOLS_EXPORT QStringList createLanguageOptionGcc(ProjectFile::Kind fileKind, bool objcExt);
 
 class CPPTOOLS_EXPORT CompilerOptionsBuilder
 {