Define __tls_get_addr as a hidden symbol even for ARM or MIPS.

[ruiu]

Summary

addIgnored defines a given symbol even if there is no existing
symbol with the same name. So, even if libc provides __tls_get_addr,
we should still be able to call addIgnored.

[peter.smith]

I agree that the code is now redundant and can be removed. It used to be the case that addIgnored() would define the symbol even when there was an existing definition and cause a duplicate error. It looks like this was later fixed in -r287125 Don't error if __tls_get_addr is defined.

Apologies for the delay in responding, I've just come back from Easter break.

lld/ELF/Writer.cpp

template <class ELFT> void Writer<ELFT>::addReservedSymbols() {
   // an undefined symbol in the .o files.
   // Given that the symbol is effectively unused, we just create a dummy
   // hidden one to avoid the undefined symbol error.
   Symtab<ELFT>::X->addIgnored("_GLOBAL_OFFSET_TABLE_");
 
   // __tls_get_addr is defined by the dynamic linker for dynamic ELFs. For
   // static linking the linker is required to optimize away any references to
   // __tls_get_addr, so it's not defined anywhere. Create a hidden definition
-  // to avoid the undefined symbol error. As usual special cases are ARM and
-  // MIPS - the libc for these targets defines __tls_get_addr itself because
-  // there are no TLS optimizations for these targets.
-  if (!In<ELFT>::DynSymTab &&
-      (Config->EMachine != EM_MIPS && Config->EMachine != EM_ARM))
+  // to avoid the undefined symbol error.
+  if (!In<ELFT>::DynSymTab)
     Symtab<ELFT>::X->addIgnored("__tls_get_addr");
 
   // If linker script do layout we do not need to create any standart symbols.
   if (Script->Opt.HasSections)
     return;
 
   // __ehdr_start is the location of ELF file headers.
   addOptionalRegular<ELFT>("__ehdr_start", Out::ElfHeader, 0, STV_HIDDEN);