Change v4 exceptions to use the common C++ ABIs foreign exceptions

On platforms where we use the common C++ ABI, throw the exception not using a
dummy C++ exception structure and the throw keyboard, but instead use the
lower-level _Unwind_RaiseException to throw a foreign exception.  It is caught
with the existing "catch (...)" and re-throw is implemented similarly, by
grabbing the current exception from the globals (a standardized data structure)
and re-throwing it.

On platforms such as ARM that lack hooks for supplying our unwind tables to the
system run-time, this patch will make it possible to link the unwinder
statically into libQtQml (libgcc or libunwind) and thus force it to use our
unwind tables, because throwing or re-throwing will always go through our
statically linked code through direct calls to _Unwind_RaiseException (instead
of libstdc++).

Change-Id: Ic2ac056fc7ed9e93fb51e30ab45f35b260487c5f
Reviewed-by: Lars Knoll <lars.knoll@digia.com>

1 files changed, 5 insertions, 6 deletions

diff --git a/src/qml/jsruntime/jsruntime.pri b/src/qml/jsruntime/jsruntime.pri
index 1739765009..88cd3a99b0 100644
--- a/src/qml/jsruntime/jsruntime.pri
+++ b/src/qml/jsruntime/jsruntime.pri
@@ -112,12 +112,11 @@ linux*|mac {
     LIBS += -ldl
 }
 
-# Only on Android/ARM at the moment, because only there we have issues
-# replacing __gnu_Unwind_Find_exidx with our own implementation,
-# and thus require static libgcc linkage.
-android:equals(QT_ARCH, "arm"):*g++* {
-    static_libgcc = $$system($$QMAKE_CXX -print-file-name=libgcc.a)
-    LIBS += $$static_libgcc
+!win32:!ios {
+    *g++*:equals(QT_ARCH, "arm") {
+        static_libgcc = $$system($$QMAKE_CXX -print-file-name=libgcc.a)
+        LIBS += $$static_libgcc
+    }
     SOURCES += $$PWD/qv4exception_gcc.cpp
     DEFINES += V4_CXX_ABI_EXCEPTION
 }