Fix ubsan error that shift amount 64 is too large.

llvm-svn: 316863

diff --git a/lld/ELF/InputFiles.cpp b/lld/ELF/InputFiles.cpp
index 9b884d9..24ab052 100644 (file)
--- a/lld/ELF/InputFiles.cpp
+++ b/lld/ELF/InputFiles.cpp
@@ -763,7 +763,9 @@ template <class ELFT> void SharedFile<ELFT>::parseRest() {
     // files because the loader takes care of it. However, if we promote a
     // DSO symbol to point to .bss due to copy relocation, we need to keep
     // the original alignment requirements. We infer it here.
-    uint32_t Alignment = 1ULL << countTrailingZeros((uint64_t)Sym.st_value);
+    uint32_t Alignment = 1;
+    if (Sym.st_value)
+      Alignment = 1ULL << countTrailingZeros((uint64_t)Sym.st_value);
     if (0 < Sym.st_shndx && Sym.st_shndx < Sections.size()) {
       uint32_t SecAlign = Sections[Sym.st_shndx].sh_addralign;
       Alignment = std::min(Alignment, SecAlign);