[PATCH] D142547: [LLD] cleans up context and symbol table to allow multiple invocations to lld::elf::linker()

[Balint Joo via Phabricator via llvm-commits]

bjoo created this revision.
bjoo added reviewers: jhuber6, jdoerfert.
bjoo added a project: lld.
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Fixes: https://github.com/llvm/llvm-project/issues/59874

Initially after the first invocation of the linker() the symbol table is not cleared and this causes issues with the second invocation when linking a new shared library due to a conflict in the presence of a previously existing `_DYNAMIC` symbol tripping a runtime assertion.
The linker already had a cleanup lambda registered in an error handler. This patch just declares that lambda up front, and calls it before registering in the error handler. This way the linker can be called multiple times. This is necessary when JIT-ing e.g. AMDGCN kernels.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D142547

Files:
  lld/ELF/Driver.cpp


Index: lld/ELF/Driver.cpp
===================================================================
--- lld/ELF/Driver.cpp
+++ lld/ELF/Driver.cpp
@@ -112,8 +112,7 @@
   // This driver-specific context will be freed later by lldMain().
   auto *ctx = new CommonLinkerContext;
 
-  ctx->e.initialize(stdoutOS, stderrOS, exitEarly, disableOutput);
-  ctx->e.cleanupCallback = []() {
+  auto cleanup = []() {
     elf::ctx.reset();
     symtab = SymbolTable();
 
@@ -128,6 +127,13 @@
 
     SharedFile::vernauxNum = 0;
   };
+
+  // Clears leftovers from any previous invocation
+  cleanup();
+
+  ctx->e.initialize(stdoutOS, stderrOS, exitEarly, disableOutput);
+  ctx->e.cleanupCallback = cleanup;
+
   ctx->e.logName = args::getFilenameWithoutExe(args[0]);
   ctx->e.errorLimitExceededMsg = "too many errors emitted, stopping now (use "
                                  "--error-limit=0 to see all errors)";


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