[Bug c++/69874] Program crashes when an exception is thrown to second base class reference

[trippels at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69874

Markus Trippelsdorf <trippels at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |hjl.tools at gmail dot com

--- Comment #5 from Markus Trippelsdorf <trippels at gcc dot gnu.org> ---
Ah the misalignment will be fixed for 4.9.4, PR58066.

H.J.:

sysdeps/x86_64/dl-trampoline.S says:

 23 #ifndef DL_STACK_ALIGNMENT                                                  
 24 /* Due to GCC bug:                                                          
 25                                                                             
 26    https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58066                       
 27                                                                             
 28    __tls_get_addr may be called with 8-byte stack alignment.  Although      
 29    this bug has been fixed in GCC 4.9.4, 5.3 and 6, we can't assume         
 30    that stack will be always aligned at 16 bytes.  We use unaligned         
 31    16-byte move to load and store SSE registers, which has no penalty       
 32    on modern processors if stack is 16-byte aligned.  */                    
 33 # define DL_STACK_ALIGNMENT 8                                               
 34 #endif                                                                      
 35                                                                             
 36 #ifndef DL_RUNIME_UNALIGNED_VEC_SIZE                                        
 37 /* The maximum size of unaligned vector load and store.  */                 
 38 # define DL_RUNIME_UNALIGNED_VEC_SIZE 16                                    
 39 #endif                                                                      
 40                                                                             
 41 /* True if _dl_runtime_resolve should align stack to VEC_SIZE bytes.  */    
 42 #define DL_RUNIME_RESOLVE_REALIGN_STACK \                                   
 43   (VEC_SIZE > DL_STACK_ALIGNMENT \                                          
 44    && VEC_SIZE > DL_RUNIME_UNALIGNED_VEC_SIZE)                              

this apparently doesn't work for _dl_runtime_resolve_sse.