diff mbox series

Darwin: Handle the fPIE option specially.

Message ID 20231026072638.96201-1-iain@sandoe.co.uk
State Unresolved
Headers
Series Darwin: Handle the fPIE option specially. |

Checks

Context Check Description
snail/gcc-patch-check warning Git am fail log

Commit Message

Iain Sandoe Oct. 26, 2023, 7:26 a.m. UTC 
  Testing the fhardened patch prompted checking of what the Xcode tools
actually emit for -fPIE.  This patch makes the GCC port follow the same
pattern.  Tested on x86_64, i686-darwin, pushed to trunk, thanks,
Iain

--- 8< ---

For Darwin, PIE requires PIC codegen, but otherwise is only a link-time
change. For almost all Darwin, we do not report __PIE__; the exception is
32bit X86 and from Darwin12 to 17 only (32 bit is no longer supported
after Darwin17).

gcc/ChangeLog:

	* config/darwin.cc (darwin_override_options): Handle fPIE.

Signed-off-by: Iain Sandoe <iain@sandoe.co.uk>
---
 gcc/config/darwin.cc | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/gcc/config/darwin.cc b/gcc/config/darwin.cc
index a80b6caf95a..621a94d74a2 100644
--- a/gcc/config/darwin.cc
+++ b/gcc/config/darwin.cc
@@ -3325,6 +3325,8 @@  darwin_override_options (void)
     {
       if (strverscmp (darwin_macosx_version_min, "10.14") >= 0)
 	generating_for_darwin_version = 18;
+      else if (strverscmp (darwin_macosx_version_min, "10.8") >= 0)
+	generating_for_darwin_version = 12;
       else if (strverscmp (darwin_macosx_version_min, "10.7") >= 0)
 	generating_for_darwin_version = 11;
       else if (strverscmp (darwin_macosx_version_min, "10.6") >= 0)
@@ -3495,8 +3497,17 @@  darwin_override_options (void)
       && dwarf_debuginfo_p ())
     flag_var_tracking_uninit = flag_var_tracking;
 
-  /* Final check on PCI options; for Darwin these are not dependent on the PIE
-     ones, although PIE does require PIC to support it.  */
+  if (OPTION_SET_P (flag_pie) && flag_pie)
+    {
+      /* This is a little complicated, to match Xcode tools.
+	 For Darwin, PIE requires PIC codegen, but otherwise is only a link-
+	 time change.  For almost all Darwin, we do not report __PIE__; the
+	 exception is Darwin12-17 and for 32b only.  */
+      flag_pie = generating_for_darwin_version >= 12 && !TARGET_64BIT ? 2 : 0;
+      flag_pic = 2; /* We always set this.  */
+    }
+
+  /* Final check on PIC options.  */
   if (MACHO_DYNAMIC_NO_PIC_P)
     {
       if (flag_pic)