[WebAssembly][lld] Fix crash when applying relocations to debug sections
Debug sections are special in that they can contain relocations against
symbols that are not present in the final output (i.e. not live).
However it is also possible to have R_WASM_TABLE_INDEX relocations
against symbols that don't have a table index assigned (since they are
not address taken by actual code.
Fixes: https://github.com/emscripten-core/emscripten/issues/9023
Differential Revision: https://reviews.llvm.org/D66435
git-svn-id: https://llvm.org/svn/llvm-project/lld/trunk@369423 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/wasm/debuginfo-relocs.s b/test/wasm/debuginfo-relocs.s
new file mode 100644
index 0000000..bece55f
--- /dev/null
+++ b/test/wasm/debuginfo-relocs.s
@@ -0,0 +1,23 @@
+# RUN: llvm-mc -filetype=obj -triple=wasm32-unknown-unknown -o %t.o %s
+# RUN: wasm-ld %t.o -o %t.wasm
+# RUN: obj2yaml %t.wasm | FileCheck %s
+
+bar:
+ .functype bar () -> ()
+ end_function
+
+ .globl _start
+_start:
+ .functype _start () -> ()
+ call bar
+ end_function
+
+ .section .debug_info,"",@
+ .int32 bar
+
+# Even though `bar` is live in the final binary it doesn't have a table entry
+# since its not address taken in the code. In this case any relocations in the
+# debug sections see a address of zero.
+
+# CHECK: Name: .debug_info
+# CHECK-NEXT: Payload: '00000000'
diff --git a/wasm/InputChunks.cpp b/wasm/InputChunks.cpp
index d37b58a..9bd75df 100644
--- a/wasm/InputChunks.cpp
+++ b/wasm/InputChunks.cpp
@@ -100,7 +100,7 @@
verifyRelocTargets();
#endif
- LLVM_DEBUG(dbgs() << "applying relocations: " << getName()
+ LLVM_DEBUG(dbgs() << "applying relocations: " << toString(this)
<< " count=" << relocations.size() << "\n");
int32_t off = outputOffset - getInputSectionOffset();
diff --git a/wasm/InputFiles.cpp b/wasm/InputFiles.cpp
index 33ae332..6ec4b9d 100644
--- a/wasm/InputFiles.cpp
+++ b/wasm/InputFiles.cpp
@@ -166,7 +166,7 @@
case R_WASM_TABLE_INDEX_I32:
case R_WASM_TABLE_INDEX_SLEB:
case R_WASM_TABLE_INDEX_REL_SLEB:
- if (config->isPic && !getFunctionSymbol(reloc.Index)->hasTableIndex())
+ if (!getFunctionSymbol(reloc.Index)->hasTableIndex())
return 0;
return getFunctionSymbol(reloc.Index)->getTableIndex();
case R_WASM_MEMORY_ADDR_SLEB:
