ELF: Omit PT_GNU_STACK segment if -z execstack is provided.
In the previous patch (r254003), I made the linker emit PT_GNU_STACK
unconditionally. But sometimes you want to have a control over the
presence of the segment. With this patch, you can omit the segment
by passing -z execstack option.
llvm-svn: 254039
diff --git a/lld/ELF/Writer.cpp b/lld/ELF/Writer.cpp
index b24b4ed..fba35fb 100644
--- a/lld/ELF/Writer.cpp
+++ b/lld/ELF/Writer.cpp
@@ -933,12 +933,11 @@
// PT_GNU_STACK is a special section to tell the loader to make the
// pages for the stack non-executable.
- Elf_Phdr *PH = &Phdrs[++PhdrIdx];
- PH->p_type = PT_GNU_STACK;
- if (Config->ZExecStack)
- PH->p_flags = PF_R | PF_W | PF_X;
- else
+ if (!Config->ZExecStack) {
+ Elf_Phdr *PH = &Phdrs[++PhdrIdx];
+ PH->p_type = PT_GNU_STACK;
PH->p_flags = PF_R | PF_W;
+ }
// Fix up PT_INTERP as we now know the address of .interp section.
if (Interp) {
@@ -962,11 +961,13 @@
// Returns the number of PHDR entries.
template <class ELFT> int Writer<ELFT>::getPhdrsNum() const {
bool Tls = false;
- int I = 3; // 3 for PT_PHDR, first PT_LOAD and PT_GNU_STACK
+ int I = 2; // 2 for PT_PHDR and first PT_LOAD
if (needsInterpSection())
++I;
if (isOutputDynamic())
++I;
+ if (!Config->ZExecStack)
+ ++I;
uintX_t Last = PF_R;
for (OutputSectionBase<ELFT> *Sec : OutputSections) {
if (!needsPhdr<ELFT>(Sec))