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author | Rafael Espindola <rafael.espindola@gmail.com> | 2014-03-27 15:26:56 +0000 |
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committer | Rafael Espindola <rafael.espindola@gmail.com> | 2014-03-27 15:26:56 +0000 |
commit | f165cf7ce8d8df9b136604b1542dd9b4980793fe (patch) | |
tree | 0049f124f77c4db55402d5a0a6725fdeb6bf59f5 /lib/CodeGen/SelectionDAG/SelectionDAG.cpp | |
parent | 16dc6ed33f425fd90ecedb4b8503905ca9af5fd6 (diff) | |
download | llvm-f165cf7ce8d8df9b136604b1542dd9b4980793fe.tar.gz llvm-f165cf7ce8d8df9b136604b1542dd9b4980793fe.tar.bz2 llvm-f165cf7ce8d8df9b136604b1542dd9b4980793fe.tar.xz |
Prevent alias from pointing to weak aliases.
This adds back r204781.
Original message:
Aliases are just another name for a position in a file. As such, the
regular symbol resolutions are not applied. For example, given
define void @my_func() {
ret void
}
@my_alias = alias weak void ()* @my_func
@my_alias2 = alias void ()* @my_alias
We produce without this patch:
.weak my_alias
my_alias = my_func
.globl my_alias2
my_alias2 = my_alias
That is, in the resulting ELF file my_alias, my_func and my_alias are
just 3 names pointing to offset 0 of .text. That is *not* the
semantics of IR linking. For example, linking in a
@my_alias = alias void ()* @other_func
would require the strong my_alias to override the weak one and
my_alias2 would end up pointing to other_func.
There is no way to represent that with aliases being just another
name, so the best solution seems to be to just disallow it, converting
a miscompile into an error.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204934 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/CodeGen/SelectionDAG/SelectionDAG.cpp')
-rw-r--r-- | lib/CodeGen/SelectionDAG/SelectionDAG.cpp | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp index 61961d8ca2..52806235fd 100644 --- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp +++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp @@ -1172,7 +1172,7 @@ SDValue SelectionDAG::getGlobalAddress(const GlobalValue *GV, SDLoc DL, if (!GVar) { // If GV is an alias then use the aliasee for determining thread-localness. if (const GlobalAlias *GA = dyn_cast<GlobalAlias>(GV)) - GVar = dyn_cast_or_null<GlobalVariable>(GA->resolveAliasedGlobal(false)); + GVar = dyn_cast_or_null<GlobalVariable>(GA->getAliasedGlobal()); } unsigned Opc; |