The PIC and PIE levels are not independent. In fact, if PIE is defined
it is always the same as PIC.
This is clear in the driver where ParsePICArgs returns a PIC level and
a IsPIE boolean. Unfortunately that is currently lost and we pass two
redundant levels down the pipeline.
This patch keeps a bool and a PIC level all the way down to codegen.
llvm-svn: 273566
First, this patch cleans up the parsing of the PIC and PIE family of
options in the driver. The existing logic failed to claim arguments all
over the place resulting in kludges that marked the options as unused.
Instead actually walk all of the arguments and claim them properly.
We now treat -f{,no-}{pic,PIC,pie,PIE} as a single set, accepting the
last one on the commandline. Previously there were lots of ordering bugs
that could creep in due to the nature of the parsing. Let me know if
folks would like weird things such as "-fPIE -fno-pic" to turn on PIE,
but disable full PIC. This doesn't make any sense to me, but we could in
theory support it.
Options that seem to have intentional "trump" status (-static, -mkernel,
etc) continue to do so and are commented as such.
Next, a -pie-level flag is threaded into the frontend, rigged to
a language option, and handled preprocessor, setting up the appropriate
defines. We'll now have the correct defines when compiling with -fpie.
The one place outside of the preprocessor that was inspecting the PIC
level (as opposed to the relocation model, which is set and handled
separately, yay!) is in the GNU ObjC runtime. I changed it to exactly
preserve existing behavior. If folks want to change its behavior in the
face of PIE, they can do that in a separate patch.
Essentially the only functionality changed here is the preprocessor
defines and bug-fixes to the argument management.
Tests have been updated and extended to test all of this a bit more
thoroughly.
llvm-svn: 154291
testing any of the strange driver behavior. We already have some tiny
tests for the driver behavior, and I'm going to expand them greatly in
the next commit.
llvm-svn: 154290
- Add -pic-level clang-cc option to specify the value for the define,
updated driver to pass this.
- Added __pic__
- Added OBJC_ZEROCOST_EXCEPTIONS define while I was here (to match gcc).
llvm-svn: 68584
Rafael Espindola