[LLVMdev] Build failure with libcxx

[İsmail Dönmez]

I did a diff -u broken.ii working.ii and the difference explains the
problem:

@@ -36617,7 +36628,7 @@
     } x;
   };
   return Allocator.Allocate(
-      Size, std::min((size_t)llvm::NextPowerOf2(Size), offsetof(S, x)));
+      Size, std::min((size_t)llvm::NextPowerOf2(Size),
__builtin_offsetof(S, x)));
 }


Looks like non-working clang is using offsetof where-as the working one
uses __builtin_offsetof



On Fri, May 9, 2014 at 11:38 AM, İsmail Dönmez <ismail at donmez.ws> wrote:

> Hi,
>
> Recently my libcxx enabled llvm/clang builds has started to fail in
> stage2. I must admit I am stomped because I cannot make sense of the error:
>
> [  723s] FAILED: /home/abuild/rpmbuild/BUILD/llvm/stage1/bin/clang++
> -DLLVMSupport_EXPORTS -DNDEBUG -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS
> -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -stdlib=libc++ -fPIC
> -fvisibility-inlines-hidden -Wall -W -Wno-unused-parameter -Wwrite-strings
> -Wmissing-field-initializers -pedantic -Wno-long-long
> -Wcovered-switch-default -Wnon-virtual-dtor -std=c++11 -fcolor-diagnostics
> -ffunction-sections -fdata-sections -O2 -g -DNDEBUG -fPIC -Ilib/Support
> -I../lib/Support -Iinclude -I../include    -fno-exceptions -MMD -MT
> lib/Support/CMakeFiles/LLVMSupport.dir/Allocator.cpp.o -MF
> lib/Support/CMakeFiles/LLVMSupport.dir/Allocator.cpp.o.d -o
> lib/Support/CMakeFiles/LLVMSupport.dir/Allocator.cpp.o -c
> ../lib/Support/Allocator.cpp
> [  723s] In file included from ../lib/Support/Allocator.cpp:14:
> [  723s] ../include/llvm/Support/Allocator.h:421:65: error: 'S' does not
> refer to a value
> [  723s]       Size, std::min((size_t)llvm::NextPowerOf2(Size),
> offsetof(S, x)));
> [  723s]                                                                 ^
> [  723s] ../include/llvm/Support/Allocator.h:411:10: note: declared here
> [  723s]   struct S {
> [  723s]          ^
> [  723s] 1 error generated.
>
> clang r207403 is OK but trunk fails. Any ideas for debugging this would be
> appreciated.
>
> Thanks!
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20140511/ed45f1f1/attachment.html>