From 501769548a959077a8ad8694eef32c179e8352b1 Mon Sep 17 00:00:00 2001 From: LLVM Packaging Team Date: Tue, 9 Jul 2019 20:04:39 +0100 Subject: [PATCH] libcxxabi-arm-ehabi-fix Fix arm EHABI code to work. armhf had exception test failing without EHABI support. No known upstream bug about this. Actual code change is more like workaround than something that upstream would accept. Proper fix would be adding _Unwind_Control_Block to clang unwind.h. _Unwind_Control_Block should also extend _Unwind_Exception to make sure their ABI stays in sync. No known upstream bug about this. Gbp-Pq: Topic libcxx Gbp-Pq: Name libcxxabi-arm-ehabi-fix.patch --- libcxxabi/src/cxa_exception.cpp | 17 ++++++++++---- libcxxabi/src/cxa_exception.hpp | 39 +++++++++++++++++++++++++++++++++ 2 files changed, 52 insertions(+), 4 deletions(-) diff --git a/libcxxabi/src/cxa_exception.cpp b/libcxxabi/src/cxa_exception.cpp index 397427a02..455877098 100644 --- a/libcxxabi/src/cxa_exception.cpp +++ b/libcxxabi/src/cxa_exception.cpp @@ -262,15 +262,16 @@ __cxa_throw(void *thrown_object, std::type_info *tinfo, void (*dest)(void *)) { #ifdef __USING_SJLJ_EXCEPTIONS__ _Unwind_SjLj_RaiseException(&exception_header->unwindHeader); -#else +#elif !LIBCXXABI_ARM_EHABI _Unwind_RaiseException(&exception_header->unwindHeader); +#else + _Unwind_RaiseException(exception_header->unwindHeader); #endif // This only happens when there is no handler, or some unexpected unwinding // error happens. failed_throw(exception_header); } - // 2.5.3 Exception Handlers /* The adjusted pointer is computed by the personality routine during phase 1 @@ -533,7 +534,11 @@ void __cxa_end_catch() { // to touch a foreign exception in any way, that is undefined // behavior. They likely can't since the only way to catch // a foreign exception is with catch (...)! +#if !LIBCXXABI_ARM_EHABI _Unwind_DeleteException(&globals->caughtExceptions->unwindHeader); +#else + _Unwind_DeleteException(globals->caughtExceptions->unwindHeader); +#endif globals->caughtExceptions = 0; } } @@ -590,8 +595,10 @@ void __cxa_rethrow() { } #ifdef __USING_SJLJ_EXCEPTIONS__ _Unwind_SjLj_RaiseException(&exception_header->unwindHeader); -#else +#elif !LIBCXXABI_ARM_EHABI _Unwind_RaiseException(&exception_header->unwindHeader); +#else + _Unwind_RaiseException(exception_header->unwindHeader); #endif // If we get here, some kind of unwinding error has occurred. @@ -715,8 +722,10 @@ __cxa_rethrow_primary_exception(void* thrown_object) dep_exception_header->unwindHeader.exception_cleanup = dependent_exception_cleanup; #ifdef __USING_SJLJ_EXCEPTIONS__ _Unwind_SjLj_RaiseException(&dep_exception_header->unwindHeader); +#elif !LIBCXXABI_ARM_EHABI + _Unwind_RaiseException(&dep_exception_header->unwindHeader); #else - _Unwind_RaiseException(&dep_exception_header->unwindHeader); + _Unwind_RaiseException(dep_exception_header->unwindHeader); #endif // Some sort of unwinding error. Note that terminate is a handler. __cxa_begin_catch(&dep_exception_header->unwindHeader); diff --git a/libcxxabi/src/cxa_exception.hpp b/libcxxabi/src/cxa_exception.hpp index c8b0fb167..32440f3ad 100644 --- a/libcxxabi/src/cxa_exception.hpp +++ b/libcxxabi/src/cxa_exception.hpp @@ -24,6 +24,45 @@ static const uint64_t kOurExceptionClass = 0x434C4E47432B2B00; // CLNGC static const uint64_t kOurDependentExceptionClass = 0x434C4E47432B2B01; // CLNGC++\1 static const uint64_t get_vendor_and_language = 0xFFFFFFFFFFFFFF00; // mask for CLNGC++ +#if LIBCXXABI_ARM_EHABI +// GCC has _Unwind_Control_Block in unwind.h (unwind_arm_common.h) +#if defined(__clang__) +struct _Unwind_Control_Block +{ + uint64_t exception_class; + void (*exception_cleanup)(_Unwind_Reason_Code, _Unwind_Control_Block *); + struct { + _Unwind_Word reserved1; + _Unwind_Word reserved2; + _Unwind_Word reserved3; + _Unwind_Word reserved4; + _Unwind_Word reserved5; + } unwinder_cache; + struct { + _Unwind_Word sp; + _Unwind_Word bitpattern[5]; + } barrier_cache; + struct { + _Unwind_Word bitpattern[4]; + } cleanup_cache; + struct { + _Unwind_Word fnstart; + _Unwind_Word *ehtp; + _Unwind_Word additional; + _Unwind_Word reserved1; + } pr_cache; + long long int :0; + operator _Unwind_Exception*() noexcept + { + return reinterpret_cast<_Unwind_Exception*>(this); + } +}; + +#endif + +#define _Unwind_Exception _Unwind_Control_Block +#endif + struct _LIBCXXABI_HIDDEN __cxa_exception { #if defined(__LP64__) || defined(_LIBCXXABI_ARM_EHABI) // This is a new field to support C++ 0x exception_ptr. -- 2.30.2