Symbol alias can not be undefined in a subtraction expression #11364
Description
| Bugzilla Link | 10992 |
| Version | trunk |
| OS | MacOS X |
| Attachments | A minimal reproducer |
| CC | @asl |
Extended Description
$ cat globals.bc
; ModuleID = 'globals.cc'
target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128-n8:16:32"
target triple = "i386-apple-macosx10.6.8"
@_ZZL5IdentiE4zero = internal global { i32, [60 x i8] } zeroinitializer, align 32
@_ZZL5IdentiE4zero_asanRZ = alias internal getelementptr inbounds ({ i32, [60 x i8] }* @_ZZL5IdentiE4zero, i32 0, i32 0)
define void @_Z3foov() nounwind ssp {
entry:
%0 = volatile load i8* inttoptr (i32 lshr (i32 ptrtoint (i32* @_ZZL5IdentiE4zero_asanRZ to i32), i32 3) to i8*)
ret void
}
$ ../clang_build_Darwin/Release+Asserts/bin/clang globals.bc
fatal error: error in backend: symbol '__ZZL5IdentiE4zero_asanRZ' can not be undefined in a subtraction expression
This test case is a reduced output of the AddressSanitizer instrumentation pass (http://code.google.com/p/address-sanitizer), which works perfectly on Linux, so I suspect this to be a bug in Clang on Darwin. If necessary, I can provide a more real-world example.