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One more follow-up to r179082 - parse PIC/PIE arguments even on platfroms that force default PIC (like Darwin x86-64), otherwise specifying -fPIC will produce bogus unused argument warning 

llvm-svn: 179092
This commit is contained in:
Alexey Samsonov 2013-04-09 12:28:19 +00:00
parent 69967c2835
commit 090301e009
2 changed files with 18 additions and 13 deletions
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27
clang/lib/Driver/Tools.cpp
View File

@ -1996,22 +1996,23 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
bool PIC = PIE || getToolChain().isPICDefault();
bool IsPICLevelTwo = PIC;
// For the PIC and PIE flag options, this logic is different from the
// legacy logic in very old versions of GCC, as that logic was just
// a bug no one had ever fixed. This logic is both more rational and
// consistent with GCC's new logic now that the bugs are fixed. The last
// argument relating to either PIC or PIE wins, and no other argument is
// used. If the last argument is any flavor of the '-fno-...' arguments,
// both PIC and PIE are disabled. Any PIE option implicitly enables PIC
// at the same level.
Arg *LastPICArg =Args.getLastArg(options::OPT_fPIC, options::OPT_fno_PIC,
options::OPT_fpic, options::OPT_fno_pic,
options::OPT_fPIE, options::OPT_fno_PIE,
options::OPT_fpie, options::OPT_fno_pie);
// Check whether the tool chain trumps the PIC-ness decision. If the PIC-ness
// is forced, then neither PIC nor PIE flags will have no effect.
if (!getToolChain().isPICDefaultForced()) {
// For the PIC and PIE flag options, this logic is different from the
// legacy logic in very old versions of GCC, as that logic was just
// a bug no one had ever fixed. This logic is both more rational and
// consistent with GCC's new logic now that the bugs are fixed. The last
// argument relating to either PIC or PIE wins, and no other argument is
// used. If the last argument is any flavor of the '-fno-...' arguments,
// both PIC and PIE are disabled. Any PIE option implicitly enables PIC
// at the same level.
if (Arg *A = Args.getLastArg(options::OPT_fPIC, options::OPT_fno_PIC,
options::OPT_fpic, options::OPT_fno_pic,
options::OPT_fPIE, options::OPT_fno_PIE,
options::OPT_fpie, options::OPT_fno_pie)) {
Option O = A->getOption();
if (LastPICArg) {
Option O = LastPICArg->getOption();
if (O.matches(options::OPT_fPIC) || O.matches(options::OPT_fpic) ||
O.matches(options::OPT_fPIE) || O.matches(options::OPT_fpie)) {
PIE = O.matches(options::OPT_fPIE) || O.matches(options::OPT_fpie);

4
clang/test/Driver/pic.c
View File

@ -36,6 +36,8 @@
//
// CHECK-NO-PIE-NOT: "-pie"
//
// CHECK-NO-UNUSED-ARG-NOT: argument unused during compilation
//
// RUN: %clang -c %s -target i386-unknown-unknown -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-NO-PIC
// RUN: %clang -c %s -target i386-unknown-unknown -fpic -### 2>&1 \
@ -164,6 +166,8 @@
// RUN: | FileCheck %s --check-prefix=CHECK-PIC2
// RUN: %clang -c %s -target x86_64-apple-darwin -fPIE -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-PIC2
// RUN: %clang -c %s -target x86_64-apple-darwin -fPIC -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-NO-UNUSED-ARG
//
// Darwin gets even more special with '-mdynamic-no-pic'. This flag is only
// valid on Darwin, and it's behavior is very strange but needs to remain