lld: Set DF_1_PIE for -pie

DF_1_PIE originated from Solaris[1].

GNU ld[2] sets the flag on non-Solaris platforms.

It can help distinguish PIE from ET_DYN.
eu-classify from elfutils uses this to recognize PIE[3].

glibc uses this flag to reject dlopen'ing a PIE[4]

[1] https://docs.oracle.com/cd/E36784_01/html/E36857/chapter6-42444.html
[2] https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=5fe2850dd96483f176858fd75c098313d5b20bc2
[3] https://sourceware.org/git/?p=elfutils.git;a=commit;h=3f489b5c7c78df6d52f8982f79c36e9a220e8951
[4] https://sourceware.org/bugzilla/show_bug.cgi?id=24323

Discussed with:	dim
Obtained from:	LLVM ee9a251caf1d
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
This commit is contained in:
Ed Maste 2020-06-02 22:57:13 +00:00
parent 4e99f45480
commit dfd4db9333
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=361740

View file

@ -1315,6 +1315,8 @@ template <class ELFT> void DynamicSection<ELFT>::finalizeContents() {
dtFlags1 |= DF_1_NODELETE;
if (config->zNodlopen)
dtFlags1 |= DF_1_NOOPEN;
if (config->pie)
dtFlags1 |= DF_1_PIE;
if (config->zNow) {
dtFlags |= DF_BIND_NOW;
dtFlags1 |= DF_1_NOW;