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</o:shapelayout></xml><![endif]--></head><body lang=EN-GB link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal>Hello dear community,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I’ve been trying to implement a way to set address spaces using a custom C++11-style attribute, but I’ve been running into problems. The syntax I’m trying to use is:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>[[vms::ptr_32]] int* HiIAmA32BitPtr{ (int*)0xFFFF'FFFF };<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>But apparently clang ignores those C++11-style attributes. Looking at the source, it’s because the attribute isn’t attached properly to the DeclSpec since…<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span style='font-size:9.5pt;font-family:Consolas;color:#2B91AF'>DeclaratorChunk</span><span style='font-size:9.5pt;font-family:Consolas;color:black'>& DeclType = D.getTypeObject(chunkIndex);<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.5pt;font-family:Consolas;color:black'><o:p> </o:p></span></p><p class=MsoNormal>…returns NULL. Not sure why, or what it is doing. The alternative way of doing it that I found is doing:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>int* [[vms::ptr_32]] HiIAmA32BitPtr{ (int*)0xFFFF'FFFF };<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>This attribute is detected properly, but the type passed into <span style='font-size:9.5pt;font-family:Consolas;color:black'>processTypeAttrs </span>is int* (apparently if using the __attribute((address_space)) syntax, it passes in regulator int), and attaching the address space to int* doesn’t seem to work as clang creates an llvm::type (lib/CodeGen/CodeGenTypes.cpp) using the address space of the pointee instead of the actual pointer type. That seems weird to me, but I don’t know what exactly address spaces are or how they work.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>So I’m a little confused on how to approach this. I would like the first syntax to work if possible, but I’m not sure how one would go about implementing that without breaking anything. The second syntax seems to behave in a non-ideal way, by passing in int* instead of int. Not sure how one would go about fixing that, or if one should just make a hack to try to get the underlying type. I use address spaces since it seems like a good way to use mixed pointer sizes in the same translation unit.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Any ideas or thoughts?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal style='margin-top:12.0pt;page-break-after:avoid'><span style='font-family:"Calibri Light",sans-serif;color:#A5A5A5;mso-fareast-language:EN-GB'>Regards,</span><span style='color:black;mso-fareast-language:EN-GB'><o:p></o:p></span></p><p class=MsoNormal style='page-break-after:avoid'><span style='font-family:"Calibri Light",sans-serif;color:#A5A5A5;mso-fareast-language:EN-GB'>Patrik Eklöf</span><span style='color:black;mso-fareast-language:EN-GB'><o:p></o:p></span></p></div></body></html>