Implement properties to control use of exception handling.

Task-number: QBS-387
Change-Id: Ia3d8bfe30b0362f1e7b6892cba32ddfb569bdbc4
Reviewed-by: Christian Kandeler <christian.kandeler@theqtcompany.com>

19 files changed, 157 insertions, 14 deletions

diff --git a/doc/reference/modules/android-ndk-module.qdoc b/doc/reference/modules/android-ndk-module.qdoc
index 0d9e10e52..533e3183a 100644
--- a/doc/reference/modules/android-ndk-module.qdoc
+++ b/doc/reference/modules/android-ndk-module.qdoc
@@ -97,12 +97,6 @@
         \li undefined
         \li Whether to use the hard floating point variant of the armeabi-v7a ABI.
     \row
-        \li enableExceptions
-        \li bool
-        \li 1.4
-        \li \c{appStl !== "system"}
-        \li Whether to enable exceptions in C++ code.
-    \row
         \li enableRtti
         \li bool
         \li 1.4
diff --git a/doc/reference/modules/cpp-module.qdoc b/doc/reference/modules/cpp-module.qdoc
index 49d681260..25a3a8467 100644
--- a/doc/reference/modules/cpp-module.qdoc
+++ b/doc/reference/modules/cpp-module.qdoc
@@ -329,7 +329,20 @@
             toolchain is used.
             \note For MSVC the default value is \c{"dynamic"}.
             \note At the moment this property is only functional for MSVC.
-
+    \row
+        \li enableExceptions
+        \li \c{bool}
+        \li 1.5
+        \li \c{undefined}
+        \li Whether to enable exceptions in C++ code.
+    \row
+        \li exceptionHandlingModel
+        \li \c{string}
+        \li 1.5
+        \li \c{"default"}
+        \li The exception handling model to use. For MSVC, this can be \c{"default"}, \c{"seh"} or
+            \c{"externc"}. For all other compilers, \c{"default"} indicates the default or only
+            exception handling model.
     \row
         \li enableReproducibleBuilds
         \li \c{bool}
diff --git a/share/qbs/modules/Android/ndk/ndk.qbs b/share/qbs/modules/Android/ndk/ndk.qbs
index d9ea534d5..030293ebf 100644
--- a/share/qbs/modules/Android/ndk/ndk.qbs
+++ b/share/qbs/modules/Android/ndk/ndk.qbs
@@ -77,7 +77,6 @@ Module {
         return cpp.toolchainPrefix + toolchainVersionNumber;
     }
 
-    property bool enableExceptions: appStl !== "system"
     property bool enableRtti: appStl !== "system"
     property bool hardFloat
     property string ndkDir: ndkProbe.path
@@ -206,16 +205,14 @@ Module {
 
     qbs.optimization: cpp.targetAbi === "androideabi" ? "small" : base
 
+    cpp.enableExceptions: appStl !== "system"
+
     cpp.commonCompilerFlags: NdkUtils.commonCompilerFlags(qbs.buildVariant, abi, hardFloat, armMode)
 
     cpp.linkerFlags: NdkUtils.commonLinkerFlags(abi, hardFloat)
 
     cpp.cxxFlags: {
         var flags = [];
-        if (enableExceptions)
-            flags.push("-fexceptions");
-        else
-            flags.push("-fno-exceptions");
         if (enableRtti)
             flags.push("-frtti");
         else
diff --git a/share/qbs/modules/cpp/CppModule.qbs b/share/qbs/modules/cpp/CppModule.qbs
index df10fd1dc..58bac982a 100644
--- a/share/qbs/modules/cpp/CppModule.qbs
+++ b/share/qbs/modules/cpp/CppModule.qbs
@@ -271,6 +271,9 @@ Module {
         description: "version of the C++ standard library to use"
     }
 
+    property bool enableExceptions
+    property string exceptionHandlingModel: "default"
+
     // Platform properties. Those are intended to be set by the toolchain setup
     // and are prepended to the corresponding user properties.
     property stringList platformAssemblerFlags
diff --git a/share/qbs/modules/cpp/GenericGCC.qbs b/share/qbs/modules/cpp/GenericGCC.qbs
index 1424e5297..28f2652bd 100644
--- a/share/qbs/modules/cpp/GenericGCC.qbs
+++ b/share/qbs/modules/cpp/GenericGCC.qbs
@@ -137,6 +137,26 @@ CppModule {
         return versionParts.join('.');
     }
 
+    exceptionHandlingModel: {
+        if (qbs.toolchain.contains("mingw")) {
+            // https://gcc.gnu.org/onlinedocs/cpp/Common-Predefined-Macros.html claims
+            // __USING_SJLJ_EXCEPTIONS__ is defined as 1 when using SJLJ exceptions, but there don't
+            // seem to be defines for the other models, so use the presence of the DLLs for now.
+            var prefix = toolchainInstallPath;
+            if (!qbs.hostOS.contains("windows"))
+                prefix = FileInfo.joinPaths(toolchainInstallPath, "..", "lib", "gcc",
+                                            toolchainPrefix,
+                                            [compilerVersionMajor, compilerVersionMinor].join("."));
+            var models = ["seh", "sjlj", "dw2"];
+            for (var i = 0; i < models.length; ++i) {
+                if (File.exists(FileInfo.joinPaths(prefix, "libgcc_s_" + models[i] + "-1.dll"))) {
+                    return models[i];
+                }
+            }
+        }
+        return base;
+    }
+
     validate: {
         var validator = new ModUtils.PropertyValidator("cpp");
         validator.setRequiredProperty("architecture", architecture,
diff --git a/share/qbs/modules/cpp/gcc.js b/share/qbs/modules/cpp/gcc.js
index 8c1a3160f..0154c8ac4 100644
--- a/share/qbs/modules/cpp/gcc.js
+++ b/share/qbs/modules/cpp/gcc.js
@@ -420,6 +420,18 @@ function compilerFlags(product, input, output) {
         args.push(useArc ? "-fobjc-arc" : "-fno-objc-arc");
     }
 
+    var enableExceptions = ModUtils.moduleProperty(input, "enableExceptions");
+    if (enableExceptions !== undefined) {
+        if (tag === "cpp" || tag === "objcpp")
+            args.push(enableExceptions ? "-fexceptions" : "-fno-exceptions");
+
+        if (tag === "objc" || tag === "objcpp") {
+            args.push(enableExceptions ? "-fobjc-exceptions" : "-fno-objc-exceptions");
+            if (useArc !== undefined)
+                args.push(useArc ? "-fobjc-arc-exceptions" : "-fno-objc-arc-exceptions");
+        }
+    }
+
     var visibility = ModUtils.moduleProperty(input, 'visibility');
     if (!product.type.contains('staticlibrary')
             && !product.moduleProperty("qbs", "toolchain").contains("mingw")) {
diff --git a/share/qbs/modules/cpp/msvc.js b/share/qbs/modules/cpp/msvc.js
index aff810c27..70636aa3b 100644
--- a/share/qbs/modules/cpp/msvc.js
+++ b/share/qbs/modules/cpp/msvc.js
@@ -47,8 +47,22 @@ function prepareCompiler(project, product, inputs, outputs, input, output) {
     // Whether we're compiling a precompiled header or normal source file
     var pchOutput = outputs[tag + "_pch"] ? outputs[tag + "_pch"][0] : undefined;
 
-    // enable unwind semantics
-    args.push("/EHsc")
+    var enableExceptions = ModUtils.moduleProperty(input, "enableExceptions");
+    if (enableExceptions) {
+        var ehModel = ModUtils.moduleProperty(input, "exceptionHandlingModel");
+        switch (ehModel) {
+        case "default":
+            args.push("/EHsc"); // "Yes" in VS
+            break;
+        case "seh":
+            args.push("/EHa"); // "Yes with SEH exceptions" in VS
+            break;
+        case "externc":
+            args.push("/EHs"); // "Yes with Extern C functions" in VS
+            break;
+        }
+    }
+
     // optimization:
     if (optimization === 'small')
         args.push('/Os')
diff --git a/tests/auto/blackbox/testdata/enableExceptions/empty.m b/tests/auto/blackbox/testdata/enableExceptions/empty.m
new file mode 100644
index 000000000..d3714dc09
--- /dev/null
+++ b/tests/auto/blackbox/testdata/enableExceptions/empty.m
@@ -0,0 +1 @@
+int main2() { return 0; }
diff --git a/tests/auto/blackbox/testdata/enableExceptions/empty.mm b/tests/auto/blackbox/testdata/enableExceptions/empty.mm
new file mode 100644
index 000000000..fe94a49a3
--- /dev/null
+++ b/tests/auto/blackbox/testdata/enableExceptions/empty.mm
@@ -0,0 +1 @@
+int main3() { return 0; }
diff --git a/tests/auto/blackbox/testdata/enableExceptions/emptymain.cpp b/tests/auto/blackbox/testdata/enableExceptions/emptymain.cpp
new file mode 100644
index 000000000..76e819701
--- /dev/null
+++ b/tests/auto/blackbox/testdata/enableExceptions/emptymain.cpp
@@ -0,0 +1 @@
+int main() { return 0; }
diff --git a/tests/auto/blackbox/testdata/enableExceptions/exceptions-objc.qbs b/tests/auto/blackbox/testdata/enableExceptions/exceptions-objc.qbs
new file mode 100644
index 000000000..74738ad12
--- /dev/null
+++ b/tests/auto/blackbox/testdata/enableExceptions/exceptions-objc.qbs
@@ -0,0 +1,6 @@
+import qbs
+
+CppApplication {
+    files: ["main.m"]
+    cpp.frameworks: ["Foundation"]
+}
diff --git a/tests/auto/blackbox/testdata/enableExceptions/exceptions-objcpp-cpp.qbs b/tests/auto/blackbox/testdata/enableExceptions/exceptions-objcpp-cpp.qbs
new file mode 100644
index 000000000..679cdebbe
--- /dev/null
+++ b/tests/auto/blackbox/testdata/enableExceptions/exceptions-objcpp-cpp.qbs
@@ -0,0 +1,6 @@
+import qbs
+
+CppApplication {
+    files: ["main.cpp"]
+    fileTags: ["objcpp"]
+}
diff --git a/tests/auto/blackbox/testdata/enableExceptions/exceptions-objcpp.qbs b/tests/auto/blackbox/testdata/enableExceptions/exceptions-objcpp.qbs
new file mode 100644
index 000000000..6856f53bb
--- /dev/null
+++ b/tests/auto/blackbox/testdata/enableExceptions/exceptions-objcpp.qbs
@@ -0,0 +1,7 @@
+import qbs
+
+CppApplication {
+    files: ["main.m"]
+    fileTags: ["objcpp"]
+    cpp.frameworks: ["Foundation"]
+}
diff --git a/tests/auto/blackbox/testdata/enableExceptions/exceptions.qbs b/tests/auto/blackbox/testdata/enableExceptions/exceptions.qbs
new file mode 100644
index 000000000..da6fdbc2d
--- /dev/null
+++ b/tests/auto/blackbox/testdata/enableExceptions/exceptions.qbs
@@ -0,0 +1,7 @@
+import qbs
+
+CppApplication {
+    files: ["main.cpp"]
+    cpp.treatWarningsAsErrors: true
+    cpp.defines: qbs.toolchain.contains("msvc") && !cpp.enableExceptions ? ["FORCE_FAIL_VS"] : []
+}
diff --git a/tests/auto/blackbox/testdata/enableExceptions/main.cpp b/tests/auto/blackbox/testdata/enableExceptions/main.cpp
new file mode 100644
index 000000000..1b99ea96d
--- /dev/null
+++ b/tests/auto/blackbox/testdata/enableExceptions/main.cpp
@@ -0,0 +1,8 @@
+#include <stdexcept>
+
+int main() {
+#ifdef FORCE_FAIL_VS
+#error "Microsoft Visual C++ cannot disable exceptions at compile-time"
+#endif
+    throw std::runtime_error("failed");
+}
diff --git a/tests/auto/blackbox/testdata/enableExceptions/main.m b/tests/auto/blackbox/testdata/enableExceptions/main.m
new file mode 100644
index 000000000..86b45fc37
--- /dev/null
+++ b/tests/auto/blackbox/testdata/enableExceptions/main.m
@@ -0,0 +1,5 @@
+#import <Foundation/Foundation.h>
+
+int main() {
+    @throw [NSError new];
+}
diff --git a/tests/auto/blackbox/testdata/enableExceptions/none.qbs b/tests/auto/blackbox/testdata/enableExceptions/none.qbs
new file mode 100644
index 000000000..102e4c261
--- /dev/null
+++ b/tests/auto/blackbox/testdata/enableExceptions/none.qbs
@@ -0,0 +1,5 @@
+import qbs
+
+CppApplication {
+    files: ["emptymain.cpp", "empty.m", "empty.mm"]
+}
diff --git a/tests/auto/blackbox/tst_blackbox.cpp b/tests/auto/blackbox/tst_blackbox.cpp
index 98765d9e1..dc34aeb28 100644
--- a/tests/auto/blackbox/tst_blackbox.cpp
+++ b/tests/auto/blackbox/tst_blackbox.cpp
@@ -3171,6 +3171,47 @@ void TestBlackbox::embedInfoPlist()
     QVERIFY(getEmbeddedBinaryPlist(defaultInstallRoot + "/mod.bundle").isEmpty());
 }
 
+void TestBlackbox::enableExceptions()
+{
+    QFETCH(QString, file);
+    QFETCH(bool, enable);
+    QFETCH(bool, expectSuccess);
+
+    QDir::setCurrent(testDataDir + QStringLiteral("/enableExceptions"));
+
+    QbsRunParameters params;
+    params.arguments = QStringList() << "-f" << file << (QStringLiteral("cpp.enableExceptions:")
+                                                         + (enable ? "true" : "false"));
+    params.expectFailure = !expectSuccess;
+    rmDirR(relativeBuildDir());
+    if (!params.expectFailure)
+        QCOMPARE(runQbs(params), 0);
+    else
+        QVERIFY(runQbs(params) != 0);
+}
+
+void TestBlackbox::enableExceptions_data()
+{
+    QTest::addColumn<QString>("file");
+    QTest::addColumn<bool>("enable");
+    QTest::addColumn<bool>("expectSuccess");
+
+    QTest::newRow("no exceptions, enabled") << "none.qbs" << true << true;
+    QTest::newRow("no exceptions, disabled") << "none.qbs" << false << true;
+
+    QTest::newRow("C++ exceptions, enabled") << "exceptions.qbs" << true << true;
+    QTest::newRow("C++ exceptions, disabled") << "exceptions.qbs" << false << false;
+
+    if (HostOsInfo::isOsxHost()) {
+        QTest::newRow("Objective-C exceptions, enabled") << "exceptions-objc.qbs" << true << true;
+        QTest::newRow("Objective-C exceptions in Objective-C++ source, enabled") << "exceptions-objcpp.qbs" << true << true;
+        QTest::newRow("C++ exceptions in Objective-C++ source, enabled") << "exceptions-objcpp-cpp.qbs" << true << true;
+        QTest::newRow("Objective-C, disabled") << "exceptions-objc.qbs" << false << false;
+        QTest::newRow("Objective-C exceptions in Objective-C++ source, disabled") << "exceptions-objcpp.qbs" << false << false;
+        QTest::newRow("C++ exceptions in Objective-C++ source, disabled") << "exceptions-objcpp-cpp.qbs" << false << false;
+    }
+}
+
 void TestBlackbox::frameworkStructure()
 {
     if (!HostOsInfo::isOsxHost())
diff --git a/tests/auto/blackbox/tst_blackbox.h b/tests/auto/blackbox/tst_blackbox.h
index 770ffed5f..0ac257b88 100644
--- a/tests/auto/blackbox/tst_blackbox.h
+++ b/tests/auto/blackbox/tst_blackbox.h
@@ -120,6 +120,8 @@ private slots:
     void dynamicMultiplexRule();
     void dynamicRuleOutputs();
     void embedInfoPlist();
+    void enableExceptions();
+    void enableExceptions_data();
     void erroneousFiles_data();
     void erroneousFiles();
     void exportRule();