Sync libiberty from GCC, replaying updates to configure scripts

3 files changed, 45 insertions, 13 deletions

diff --git a/config/ChangeLog b/config/ChangeLog
index 6ffb0ed1e66..30314370241 100644
--- a/config/ChangeLog
+++ b/config/ChangeLog
@@ -1,3 +1,18 @@
+2015-04-10  Jakub Jelinek  <jakub@redhat.com>
+	    Iain Sandoe  <iain@codesourcery.com>
+
+	PR target/65351
+	* mh-darwin: Only apply -mdynamic-no-pic for m32 Darwin when the
+	compiler in use supports -mno-dynamic-no-pic.
+	* picflag.m4: Only append -mno-dynamic-no-pic for Darwin when
+	-mdynamic-no-pic is present in CFLAGS.
+
+2015-04-07  Jakub Jelinek  <jakub@redhat.com>
+	    Iain Sandoe  <iain@codesourcery.com>
+
+	PR target/65351
+	* picflag.m4: Append -mno-dynamic-no-pic for Darwin.
+
 2015-04-02  H.J. Lu  <hongjiu.lu@intel.com>
 
 	* zlib.m4 (AM_ZLIB): Set zlibdir to -L\$(top_builddir)/../zlib
diff --git a/config/mh-darwin b/config/mh-darwin
index a039f201410..148b73038c3 100644
--- a/config/mh-darwin
+++ b/config/mh-darwin
@@ -1,18 +1,29 @@
 # The -mdynamic-no-pic ensures that the compiler executable is built without
 # position-independent-code -- the usual default on Darwin. This fix speeds
-# compiles by 3-5%.
-BOOT_CFLAGS += \
+# compiles by 3-5%.  Don't add it if the compiler doesn't also support
+# -mno-dynamic-no-pic to undo it.
+DARWIN_MDYNAMIC_NO_PIC := \
 `case ${host} in i?86-*-darwin* | powerpc-*-darwin*) \
-                 echo -mdynamic-no-pic ;; esac;`
+   $(CC) -S -xc /dev/null -o /dev/null -mno-dynamic-no-pic 2>/dev/null \
+   && echo -mdynamic-no-pic ;; esac`
+DARWIN_GCC_MDYNAMIC_NO_PIC := \
+`case ${host} in i?86-*-darwin* | powerpc-*-darwin*) \
+   $(CC) -S -xc /dev/null -o /dev/null -mno-dynamic-no-pic 2>/dev/null \
+   || echo -mdynamic-no-pic ;; esac`
 
 # ld on Darwin versions >= 10.7 defaults to PIE executables. Disable this for
 # gcc components, since it is incompatible with our pch implementation.
-BOOT_LDFLAGS += \
-`case ${host} in *-*-darwin[1][1-9]*) echo -Wl,-no_pie ;; esac;`
+DARWIN_NO_PIE := `case ${host} in *-*-darwin[1][1-9]*) echo -Wl,-no_pie ;; esac;`
+
+BOOT_CFLAGS += $(DARWIN_MDYNAMIC_NO_PIC)
+BOOT_LDFLAGS += $(DARWIN_NO_PIE)
 
 # Similarly, for cross-compilation.
-STAGE1_CFLAGS += \
-`case ${host} in i?86-*-darwin* | powerpc-*-darwin*)\
-                 echo -mdynamic-no-pic ;; esac;`
-STAGE1_LDFLAGS += \
-`case ${host} in *-*-darwin[1][1-9]*) echo -Wl,-no_pie ;; esac;`
+STAGE1_CFLAGS += $(DARWIN_MDYNAMIC_NO_PIC)
+STAGE1_LDFLAGS += $(DARWIN_NO_PIE)
+
+# Without -mno-dynamic-no-pic support, add -mdynamic-no-pic just to later
+# stages when we know it is built with gcc.
+STAGE2_CFLAGS += $(DARWIN_GCC_MDYNAMIC_NO_PIC)
+STAGE3_CFLAGS += $(DARWIN_GCC_MDYNAMIC_NO_PIC)
+STAGE4_CFLAGS += $(DARWIN_GCC_MDYNAMIC_NO_PIC)
diff --git a/config/picflag.m4 b/config/picflag.m4
index 3bcdbf1de30..2f5b9721eb2 100644
--- a/config/picflag.m4
+++ b/config/picflag.m4
@@ -7,9 +7,15 @@ AC_DEFUN([_GCC_PICFLAG], [
 case "${$2}" in
     # PIC is the default on some targets or must not be used.
     *-*-darwin*)
-	# PIC is the default on this platform
-	# Common symbols not allowed in MH_DYLIB files
-	$1=-fno-common
+	# For darwin, common symbols are not allowed in MH_DYLIB files
+	case "${CFLAGS}" in
+	  # If we are using a compiler supporting mdynamic-no-pic
+	  # and the option has been tested as safe to add, then cancel
+	  # it here, since the code generated is incompatible with shared
+	  # libs.
+	  *-mdynamic-no-pic*) $1='-fno-common -mno-dynamic-no-pic' ;;
+	  *) $1=-fno-common ;;
+	esac
 	;;
     alpha*-dec-osf5*)
 	# PIC is the default.