[cfe-dev] MS style ASM failure and crash

[JB Feldman]

I'm trying to track this down, am I correct that in the example I pasted
above: "KPCR" (in the bug report, "s") should be a TypedefNameDecl?


On Thu, Feb 27, 2014 at 11:38 AM, JB Feldman <jb.feldman at kyrus-tech.com>wrote:

> Bug has been filed: http://llvm.org/bugs/show_bug.cgi?id=18994
>
>
> On Thu, Feb 27, 2014 at 10:52 AM, Reid Kleckner <rnk at google.com> wrote:
>
>> This also happens (just once) in the Chromium build:
>>
>> http://build.chromium.org/p/chromium.fyi/builders/Chromium%20Win%20Clang/builds/645/steps/compile/logs/stdio
>>
>> Parsing this involves Clang and
>> llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp.  It's really tricky because
>> C++ expressions can occur in lots of places, making it harder to parse the
>> assembly.
>>
>> Feel free to file a bug on this.
>>
>>
>> On Thu, Feb 27, 2014 at 7:22 AM, JB Feldman <jb.feldman at kyrus-tech.com>wrote:
>>
>>> Hi guys,
>>>
>>> I will file a bug report in a little bit (once I get a minimal test
>>> case) but I wanted to ask if anyone understands the problem I'm seeing.
>>>
>>> Trying to include ntddk.h and compiling with clang-cl, I get the
>>> following message:
>>>
>>> In file included from kbfiltr.c:19:
>>> In file included from ./kbfiltr.h:28:
>>> C:\WINDDK\3790.1830\inc\ddk\wxp\ntddk.h(7149,29) :  error: unexpected
>>> type name
>>>       'KPCR': expected expression
>>>     __asm {  movzx eax, _PCR KPCR.Number  }
>>>                              ^
>>> Assertion failed: End.getPointer() <= EndPtr && "frontend claimed part
>>> of a token?", file
>>> ..\..\..\..\..\lib\Target\X86\AsmParser\X86AsmParser.cpp, line 1481
>>> clang-cl.exe: error: clang frontend command failed with exit code 3 (use
>>> -v to s
>>> ee invocation)
>>>
>>> The assertion failure obviously results in a crash.
>>>
>>> So my initial guess was some kind of Lexer issue, maybe because of no
>>> semicolon, or... who knows. But then, I rewrote that code to read:
>>>
>>> int x = FIELD_OFFSET(KPCR, Number);
>>> __asm { movzx eax, fs:[x] }
>>>
>>> Which compiles to the same code, and that actually did work with
>>> clang-cl. Can anyone tell me why one works and the other doesn't? (My
>>> guess: MS not following standard Intel notation spec)
>>>
>>> Thanks,
>>> JB
>>>
>>> _______________________________________________
>>> cfe-dev mailing list
>>> cfe-dev at cs.uiuc.edu
>>> http://lists.cs.uiuc.edu/mailman/listinfo/cfe-dev
>>>
>>>
>>
>
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