[ELF] - Do not crash if symbol type set to TLS when there is no tls sections.

[grimar]

Summary

id_000021,sig_11,src_000002,op_flip1,pos_92 from PR30540

does not have TLS sections, but type
of one of the symbol is broken and set to STT_TLS,
what resulted in a crash.

[ruiu]

ELF/Symbols.cpp

64–65

fatal(getFilename(D.File) + " has a STT_TLS symbol but doesn't have a PT_TLS section.")

test/ELF/invalid/tls-symbol.s

3–4

The test file contains a STT_TLS symbol but has no TLS section.

5–6

You can write it in one line.

[grimar]

• Addressed review comments.

[ruiu]

LGTM

ELF/Symbols.cpp

if (!SC)
       return D.Value;
 
     uintX_t Offset = D.Value;
     if (D.isSection()) {
       Offset += Addend;
       Addend = 0;
     }
     uintX_t VA = (SC->OutSec ? SC->OutSec->getVA() : 0) + SC->getOffset(Offset);
-    if (D.isTls() && !Config->Relocatable)
+    if (D.isTls() && !Config->Relocatable) {
+      if (!Out<ELFT>::TlsPhdr)
+        fatal(getFilename(D.File) +
+              ": no PT_TLS program header found when met STT_TLS symbol");
       return VA - Out<ELFT>::TlsPhdr->p_vaddr;
+    }
     return VA;
   }
   case SymbolBody::DefinedCommonKind:
     return CommonInputSection<ELFT>::X->OutSec->getVA() +
            CommonInputSection<ELFT>::X->OutSecOff +
            cast<DefinedCommon>(Body).Offset;
   case SymbolBody::SharedKind: {
     auto &SS = cast<SharedSymbol<ELFT>>(Body);

test/ELF/invalid/tls-symbol.s

+# REQUIRES: x86
+
+## tls-symbol.elf does not have TLS sections, but type
+## of one of the symbol is broken and set to STT_TLS.
+# RUN: not ld.lld %S/Inputs/tls-symbol.elf \
+# RUN:   -o %t 2>&1 | FileCheck %s
+# CHECK: no PT_TLS program header found when met STT_TLS symbol