[LLD][COFF] Fix missing MergeChunk::Instances cleanup in COFF::link()
Patch by Erik McClure with a modification to rebase to HEAD.
When calling `COFF::link()` with `CanExitEarly` set to `false`, the
function needs to clean up several global variable caches to ensure that
the next invocation of the function starts from a clean slate. The
`MergeChunk::Instances` cache is missing from this cleanup code, and as
a result will create nondeterministic memory access errors and sometimes
infinite loops due to invalid memory being referenced on the next call
to `COFF::link()`.
This fix simply clears `MergeChunk::Instances` before exiting the function.
An additional review of the COFF library was made to try and find any
other missing global caches, but I was unable to find any other than
`MergeChunk`. Someone more familiar with the global variables might want
to do their own check.
This fix was made to support inNative
<https://github.com/innative-sdk/innative>'s `.wast` script compiler,
which must build multiple incremental builds. It relies on statically
linking LLD because the entire compiler must be a single statically
embeddable library, thus preventing it from being able to call LLD as a
new process.
Differential Revision: https://reviews.llvm.org/D63042
git-svn-id: https://llvm.org/svn/llvm-project/lld/trunk@362930 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/COFF/Driver.cpp b/COFF/Driver.cpp
index 19c8702..45befa6 100644
--- a/COFF/Driver.cpp
+++ b/COFF/Driver.cpp
@@ -81,6 +81,7 @@
ObjFile::Instances.clear();
ImportFile::Instances.clear();
BitcodeFile::Instances.clear();
+ memset(MergeChunk::Instances, 0, sizeof(MergeChunk::Instances));
return !errorCount();
}
