[PATCH] D23201: [ELF] - Fix for: error "invalid section index: xxx" when linking FreeBSD kernel.

[George Rimar via llvm-commits]

grimar added inline comments.

================
Comment at: ELF/InputFiles.cpp:279-280
@@ +278,4 @@
+    // situation properly.
+    if (Sec.sh_type == SHT_SYMTAB || Sec.sh_type == SHT_STRTAB ||
+        Sec.sh_type == SHT_RELA || Sec.sh_type == SHT_RELA)
+      if (!Sections[I])
----------------
ruiu wrote:
> Hmm, why did you add more conditions?
Because hpt27xx_lib.o which initially was the reason to fix all of that
contains section symbols associated with
.rela.text, .rela.rodata, .rela.data, .rela.eh_frame, .shstrtab, .symtab, .strtab
See https://llvm.org/bugs/show_bug.cgi?id=28868

Testcase also has them:
    - Type:            STT_SECTION
      Section:         .rela.text
    - Type:            STT_SECTION
      Section:         .shstrtab
    - Type:            STT_SECTION
      Section:         .symtab
    - Type:            STT_SECTION
      Section:         .strtab

================
Comment at: ELF/Writer.cpp:100-101
@@ -99,3 +99,4 @@
 template <class ELFT> void elf::reportDiscarded(InputSectionBase<ELFT> *IS) {
-  if (!Config->PrintGcSections || !IS || IS->Live)
+  if (!Config->PrintGcSections || !IS || IS->Live ||
+      IS == &InputSection<ELFT>::Discarded)
     return;
----------------
ruiu wrote:
> Why did you have to make a change to this code?
Because since these sections are mo more nullptr, but discarded, the code below is executed
and it is not possible to call IS->getFile()->getName() when IS is InputSection<ELFT>::Discarded,
because File member is null.


https://reviews.llvm.org/D23201