1 files changed, 32 insertions, 1 deletions

diff --git a/lld/ELF/LinkerScript.cpp b/lld/ELF/LinkerScript.cpp
index b7f71944..50f2d50 100644
--- a/lld/ELF/LinkerScript.cpp
+++ b/lld/ELF/LinkerScript.cpp
@@ -215,11 +215,42 @@ template <class ELFT> void LinkerScript<ELFT>::createAssignments() {
 }
 
 template <class ELFT>
+static SectionKey<ELFT::Is64Bits> createKey(InputSectionBase<ELFT> *C,
+                                            StringRef OutsecName) {
+  // When using linker script the merge rules are different.
+  // Unfortunately, linker scripts are name based. This means that expressions
+  // like *(.foo*) can refer to multiple input sections that would normally be
+  // placed in different output sections. We cannot put them in different
+  // output sections or we would produce wrong results for
+  // start = .; *(.foo.*) end = .; *(.bar)
+  // and a mapping of .foo1 and .bar1 to one section and .foo2 and .bar2 to
+  // another. The problem is that there is no way to layout those output
+  // sections such that the .foo sections are the only thing between the
+  // start and end symbols.
+
+  // An extra annoyance is that we cannot simply disable merging of the contents
+  // of SHF_MERGE sections, but our implementation requires one output section
+  // per "kind" (string or not, which size/aligment).
+  // Fortunately, creating symbols in the middle of a merge section is not
+  // supported by bfd or gold, so we can just create multiple section in that
+  // case.
+  const typename ELFT::Shdr *H = C->getSectionHdr();
+  typedef typename ELFT::uint uintX_t;
+  uintX_t Flags = H->sh_flags & (SHF_MERGE | SHF_STRINGS);
+
+  uintX_t Alignment = 0;
+  if (isa<MergeInputSection<ELFT>>(C))
+    Alignment = std::max(H->sh_addralign, H->sh_entsize);
+
+  return SectionKey<ELFT::Is64Bits>{OutsecName, /*Type*/ 0, Flags, Alignment};
+}
+
+template <class ELFT>
 void LinkerScript<ELFT>::createSections(OutputSectionFactory<ELFT> &Factory) {
   auto AddSec = [&](InputSectionBase<ELFT> *Sec, StringRef Name) {
     OutputSectionBase<ELFT> *OutSec;
     bool IsNew;
-    std::tie(OutSec, IsNew) = Factory.create(Sec, Name);
+    std::tie(OutSec, IsNew) = Factory.create(createKey(Sec, Name), Sec);
     if (IsNew)
       OutputSections->push_back(OutSec);
     return OutSec;