Clang: Add conditions for adding exceptions flag

For GCC it can be deduced from the compiler flags, so no correction is
needed.

For MSVC it can be deduced from the detected defines.

Amends 26693e82126de15145a04c3428a10f6c15120532.

Change-Id: Ie4850f328a2afdb3e5158c58f8c30a2644d9c592
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>

3 files changed, 52 insertions, 3 deletions

diff --git a/src/plugins/cpptools/compileroptionsbuilder.cpp b/src/plugins/cpptools/compileroptionsbuilder.cpp
index 0192386ddb..49457718a7 100644
--- a/src/plugins/cpptools/compileroptionsbuilder.cpp
+++ b/src/plugins/cpptools/compileroptionsbuilder.cpp
@@ -35,6 +35,7 @@
 #include <projectexplorer/projectexplorerconstants.h>
 #include <projectexplorer/projectmacro.h>
 
+#include <utils/algorithm.h>
 #include <utils/cpplanguage_details.h>
 #include <utils/fileutils.h>
 #include <utils/qtcassert.h>
@@ -137,7 +138,7 @@ QStringList CompilerOptionsBuilder::build(ProjectFile::Kind fileKind,
     addTargetTriple();
     updateFileLanguage(fileKind);
     addLanguageVersionAndExtensions();
-    enableExceptions();
+    addMsvcExceptions();
 
     addPrecompiledHeaderOptions(usePrecompiledHeaders);
     addProjectConfigFileInclude();
@@ -273,6 +274,17 @@ void CompilerOptionsBuilder::addCompilerFlags()
     add(m_compilerFlags.flags);
 }
 
+void CompilerOptionsBuilder::addMsvcExceptions()
+{
+    if (!m_clStyle)
+        return;
+    if (Utils::anyOf(m_projectPart.toolChainMacros, [](const ProjectExplorer::Macro &macro) {
+        return macro.key == "_CPPUNWIND";
+    })) {
+        enableExceptions();
+    }
+}
+
 void CompilerOptionsBuilder::enableExceptions()
 {
     // With "--driver-mode=cl" exceptions are disabled (clang 8).
diff --git a/src/plugins/cpptools/compileroptionsbuilder.h b/src/plugins/cpptools/compileroptionsbuilder.h
index ee7e373312..356adaed1c 100644
--- a/src/plugins/cpptools/compileroptionsbuilder.h
+++ b/src/plugins/cpptools/compileroptionsbuilder.h
@@ -69,6 +69,7 @@ public:
     void addExtraCodeModelFlags();
     void addPicIfCompilerFlagsContainsIt();
     void addCompilerFlags();
+    void addMsvcExceptions();
     void enableExceptions();
     void insertWrappedQtHeaders();
     void insertWrappedMingwHeaders();
diff --git a/tests/unit/unittest/compileroptionsbuilder-test.cpp b/tests/unit/unittest/compileroptionsbuilder-test.cpp
index 76fe2be066..1376bed6b8 100644
--- a/tests/unit/unittest/compileroptionsbuilder-test.cpp
+++ b/tests/unit/unittest/compileroptionsbuilder-test.cpp
@@ -650,8 +650,6 @@ TEST_F(CompilerOptionsBuilder, BuildAllOptions)
                             "-x",
                             "c++",
                             "-std=c++17",
-                            "-fcxx-exceptions",
-                            "-fexceptions",
                             "-DprojectFoo=projectBar",
                             "-I", IsPartOfHeader("wrappedQtHeaders"),
                             "-I", IsPartOfHeader(toNative("wrappedQtHeaders/QtCore").toStdString()),
@@ -683,6 +681,44 @@ TEST_F(CompilerOptionsBuilder, BuildAllOptionsCl)
                             "--target=x86_64-apple-darwin10",
                             "/TP",
                             "/std:c++17",
+                            "-fms-compatibility-version=19.00",
+                            "-DprojectFoo=projectBar",
+                            "-D__FUNCSIG__=\"\"",
+                            "-D__FUNCTION__=\"\"",
+                            "-D__FUNCDNAME__=\"\"",
+                            "-I", IsPartOfHeader("wrappedQtHeaders"),
+                            "-I", IsPartOfHeader(toNative("wrappedQtHeaders/QtCore").toStdString()),
+                            "-I", toNative("/tmp/path"),
+                            "-I", toNative("/tmp/system_path"),
+                            "/clang:-isystem",
+                            "/clang:" + toNative(CLANG_RESOURCE_DIR ""),
+                            "/clang:-isystem",
+                            "/clang:" + toNative("/tmp/builtin_path")));
+}
+
+TEST_F(CompilerOptionsBuilder, BuildAllOptionsClWithExceptions)
+{
+    projectPart.toolchainType = ProjectExplorer::Constants::MSVC_TOOLCHAIN_TYPEID;
+    projectPart.toolChainMacros.append(ProjectExplorer::Macro{"_CPPUNWIND", "1"});
+    CppTools::CompilerOptionsBuilder compilerOptionsBuilder(projectPart,
+                                                            CppTools::UseSystemHeader::No,
+                                                            CppTools::UseTweakedHeaderPaths::Yes,
+                                                            CppTools::UseLanguageDefines::No,
+                                                            CppTools::UseBuildSystemWarnings::No,
+                                                            "dummy_version",
+                                                            "");
+
+    compilerOptionsBuilder.build(ProjectFile::CXXSource, CppTools::UsePrecompiledHeaders::No);
+
+    ASSERT_THAT(compilerOptionsBuilder.options(),
+                ElementsAre("-nostdinc",
+                            "-nostdinc++",
+                            "--driver-mode=cl",
+                            "/Zs",
+                            "-m64",
+                            "--target=x86_64-apple-darwin10",
+                            "/TP",
+                            "/std:c++17",
                             "-fcxx-exceptions",
                             "-fexceptions",
                             "-fms-compatibility-version=19.00",