Build failure MSVC 14 (x86) on Boost 1.68.0 about lockfree

[timblechmann]

hmm, i don't have an msvc2015 32bit devenv at hand atm, but could you test:

diff --git a/include/boost/lockfree/detail/freelist.hpp b/include/boost/lockfree/detail/freelist.hpp
index 374b0c7..266a0a6 100644
--- a/include/boost/lockfree/detail/freelist.hpp
+++ b/include/boost/lockfree/detail/freelist.hpp
@@ -38,6 +38,7 @@ namespace detail   {
 template <typename T,
           typename Alloc = std::allocator<T>
          >
+BOOST_ALIGNMENT( 8 )
 class freelist_stack:
     Alloc
 {
diff --git a/include/boost/lockfree/stack.hpp b/include/boost/lockfree/stack.hpp
index b9e43df..3efcfc4 100644
--- a/include/boost/lockfree/stack.hpp
+++ b/include/boost/lockfree/stack.hpp
@@ -66,6 +66,7 @@ template <typename T, class A0, class A1, class A2>
 #else
 template <typename T, typename ...Options>
 #endif
+BOOST_ALIGNMENT( 8 )
 class stack
 {
 private:

?

[stefan-floeren]

The same error (out.log).

Note that I used the following patch, consistent with the other uses of BOOST_ALIGNMENT, as I get an INTERNAL COMPILER ERROR with your patch.

diff --git a/include/boost/lockfree/detail/freelist.hpp b/include/boost/lockfree/detail/freelist.hpp
index 374b0c7..77fe14d 100644
--- a/include/boost/lockfree/detail/freelist.hpp
+++ b/include/boost/lockfree/detail/freelist.hpp
@@ -38,7 +38,9 @@ namespace detail   {
 template <typename T,
           typename Alloc = std::allocator<T>
          >
-class freelist_stack:
+class
+BOOST_ALIGNMENT( 8 )
+    freelist_stack:
     Alloc
 {
     struct freelist_node
diff --git a/include/boost/lockfree/stack.hpp b/include/boost/lockfree/stack.hpp
index b9e43df..3de124d 100644
--- a/include/boost/lockfree/stack.hpp
+++ b/include/boost/lockfree/stack.hpp
@@ -66,7 +66,9 @@ template <typename T, class A0, class A1, class A2>
 #else
 template <typename T, typename ...Options>
 #endif
-class stack
+class
+BOOST_ALIGNMENT( 8 )
+    stack
 {
 private:
 #ifndef BOOST_DOXYGEN_INVOKED

[tobias-loew]

I've got the same problems with msvc 2015 x86. The problem is that msvc 2015 x86 doesn't support alignment of 8 for function parameters passed on the stack. (AFAIK they're only guaranteed to be aligned at 4-bytes and there's no way to specify parameter-alignment.)

[timblechmann]

hmm, i've tested msvc 2017 ia32, which builds fine :/

[tobias-loew]

I can also confirm that msvc 2017 x86 (and of course also x64) supports alignment for function parameters.
But msvc 2015 has issues:

• x86 doesn't support alignment at all (only 4-byte alignment is guaranteed (even for types that have a larger "natural" alignment))
• x64 supports function parameters up to "alignas(32)"; ("alignas(64)" results again in an error C2719)

IMHO removing the alignment request for msvc <= 2015 (x86) would be the best.

Just to be complete. msvc 2017 supports alignment for function parameter up to alignas(64) for both x86 and x64.

[timblechmann]

i've fixed a few issues of aligned function parameters, but i cannot see in the error message, which function fails to instantiate due to parameter alignment :/

removing alignment hints is not an option here, as it's std::atomic, that is aligned.

but does it help to force the use of boost.atomic?

[tobias-loew]

Yes, switching to boost.atomic (and adding boost namespace to all the memory_order_... solves the problem!
The reason is: in std::atomic, atomic::atomic(_Ty _Val) and atomic::operator=(_Ty _Right) takes its argument by value, while boost.atomic takes args > sizeof(void*) by const-ref!

[mmakhalaf]

We had this problem as well using boost::lockfree::queue.

As @tobias-loew did, we've added #define BOOST_LOCKFREE_FORCE_BOOST_ATOMIC before the include fixes the compiler error for us. Then undef'ing at the end of the header.

Are there any hidden caveats to doing that?

Thanks

[rooong]

I found this problem in vs2013, the really reason maybe in files:prefix.hpp and tagged_ptr_ptrcompression.hpp
the macro defined
in boost 1.67:
it is: #ifdef BOOST_ARCH_X86_64
but in boost 1.68
it is:#if BOOST_ARCH_X86_64 || defined (aarch64)

we can change to #if defined(BOOST_ARCH_X86_64) || defined (aarch64) before the include fixes the compiler error for us