Fix how --enable-host-shared adds -fPIC to compilation flags.

The --enable-host-shared configuration option is meant to add -fPIC to
compilation flags for code meant to run on the host.

Previously, I implemented this by detecting the --enable-host-shared
in each child "configure" script (as generated from configure.ac) and
conditionally appending -fPIC to makefile variables such as CFLAGS,
CXXFLAGS and LDFLAGS.

This worked when invoking "make" from each subdirectory, but not when
running "make" in the top-level directory: the top-level make would
pass in "CFLAGS=-g -O2" to the child "makes", overriding their CFLAGS,
thus erroneously omitting the "-fPIC" flag.

This patch instead adds a PICFLAG variable, set up in the child
configure scripts, to contain -fPIC if configured with
--enable-host-shared.  The PICFLAG variable is then added to an
appropriate variable in each child makefile to ensure that it is used
when building host code.

This ensures that -fPIC is present if requested, when building both
from the top-level directory, and from the child directories.

gcc/
	* Makefile.in: Set PICFLAG from configure script; add it to
	INTERNAL_CFLAGS.
	* configure.ac (--enable-host-shared): Set up PICFLAG rather
	than attempting to append -fPIC to CFLAGS, CXXFLAGS, LDFLAGS.
	* configure: Regenerate.

libcpp/
	* Makefile.in: Set PICFLAG from configure script; add it to
	ALL_CFLAGS.
	* configure.ac (--enable-host-shared): Set up PICFLAG rather
	than attempting to append -fPIC to CFLAGS, CXXFLAGS, LDFLAGS.
	* configure: Regenerate.

libdecnumber/
	* Makefile.in: Set PICFLAG from configure script; add it to
	ALL_CFLAGS.
	* configure.ac (--enable-host-shared): Set up PICFLAG rather
	than attempting to append -fPIC to CFLAGS, CXXFLAGS, LDFLAGS.
	* configure: Regenerate.

zlib/
	* Makefile.am: Add PICFLAG to libz_a_CFLAGS.
	* configure.ac (--enable-host-shared): Set up PICFLAG rather
	than attempting to append -fPIC to CFLAGS.
	* Makefile.in: Regenerate.
	* configure: Regenerate.

17 files changed, 76 insertions, 31 deletions

diff --git a/gcc/ChangeLog.jit b/gcc/ChangeLog.jit
index 5b4faf16369..e846c08625a 100644
--- a/gcc/ChangeLog.jit
+++ b/gcc/ChangeLog.jit
@@ -1,3 +1,11 @@
+2013-10-07  David Malcolm  <dmalcolm@redhat.com>
+
+	* Makefile.in: Set PICFLAG from configure script; add it to
+	INTERNAL_CFLAGS.
+	* configure.ac (--enable-host-shared): Set up PICFLAG rather
+	than attempting to append -fPIC to CFLAGS, CXXFLAGS, LDFLAGS.
+	* configure: Regenerate.
+
 2013-10-03  David Malcolm  <dmalcolm@redhat.com>
 
 	* Makefile.in (LIBIBERTY): Use pic build of libiberty.a if
diff --git a/gcc/Makefile.in b/gcc/Makefile.in
index 30585538268..eca1500e7a1 100644
--- a/gcc/Makefile.in
+++ b/gcc/Makefile.in
@@ -135,6 +135,9 @@ CFLAGS = @CFLAGS@
 CXXFLAGS = @CXXFLAGS@
 LDFLAGS = @LDFLAGS@
 
+# Should we build position-independent host code?
+PICFLAG = @PICFLAG@
+
 # Flags to determine code coverage. When coverage is disabled, this will
 # contain the optimization flags, as you normally want code coverage
 # without optimization.
@@ -957,7 +960,7 @@ CONTEXT_H = context.h
 # programs built during a bootstrap.
 # autoconf inserts -DCROSS_DIRECTORY_STRUCTURE if we are building a
 # cross compiler which does not use the native headers and libraries.
-INTERNAL_CFLAGS = -DIN_GCC @CROSS@
+INTERNAL_CFLAGS = -DIN_GCC $(PICFLAG) @CROSS@
 
 # This is the variable actually used when we compile. If you change this,
 # you probably want to update BUILD_CFLAGS in configure.ac
diff --git a/gcc/configure b/gcc/configure
index 672ae129f92..40043bb6e75 100755
--- a/gcc/configure
+++ b/gcc/configure
@@ -600,6 +600,7 @@ ac_includes_default="\
 
 ac_subst_vars='LTLIBOBJS
 LIBOBJS
+PICFLAG
 enable_host_shared
 enable_plugin
 pluginlibs
@@ -17896,7 +17897,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 17899 "configure"
+#line 17900 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -18002,7 +18003,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 18005 "configure"
+#line 18006 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -27697,17 +27698,18 @@ $as_echo "#define ENABLE_PLUGIN 1" >>confdefs.h
 fi
 
 
-# Enable --enable-host-shared, adding -fPIC
+# Enable --enable-host-shared
 # Check whether --enable-host-shared was given.
 if test "${enable_host_shared+set}" = set; then :
-  enableval=$enable_host_shared; CFLAGS="$CFLAGS -fPIC"
- CXXFLAGS="$CXXFLAGS -fPIC"
- LDFLAGS="$LDFLAGS -fPIC"
+  enableval=$enable_host_shared; PICFLAG=-fPIC
+else
+  PICFLAG=
 fi
 
 
 
 
+
 # Check whether --enable-libquadmath-support was given.
 if test "${enable_libquadmath_support+set}" = set; then :
   enableval=$enable_libquadmath_support; ENABLE_LIBQUADMATH_SUPPORT=$enableval
diff --git a/gcc/configure.ac b/gcc/configure.ac
index f1455ddb78f..5111109af48 100644
--- a/gcc/configure.ac
+++ b/gcc/configure.ac
@@ -5399,14 +5399,13 @@ if test x"$enable_plugin" = x"yes"; then
 fi
 
 
-# Enable --enable-host-shared, adding -fPIC
+# Enable --enable-host-shared
 AC_ARG_ENABLE(host-shared,
 [AS_HELP_STRING([--enable-host-shared],
 		[build host code as shared libraries])],
-[CFLAGS="$CFLAGS -fPIC"
- CXXFLAGS="$CXXFLAGS -fPIC"
- LDFLAGS="$LDFLAGS -fPIC"], [])
+[PICFLAG=-fPIC], [PICFLAG=])
 AC_SUBST(enable_host_shared)
+AC_SUBST(PICFLAG)
 
 
 AC_ARG_ENABLE(libquadmath-support,
diff --git a/libcpp/ChangeLog.jit b/libcpp/ChangeLog.jit
index fff6241658a..6f497d4888b 100644
--- a/libcpp/ChangeLog.jit
+++ b/libcpp/ChangeLog.jit
@@ -1,3 +1,11 @@
+2013-10-07  David Malcolm  <dmalcolm@redhat.com>
+
+	* Makefile.in: Set PICFLAG from configure script; add it to
+	ALL_CFLAGS.
+	* configure.ac (--enable-host-shared): Set up PICFLAG rather
+	than attempting to append -fPIC to CFLAGS, CXXFLAGS, LDFLAGS.
+	* configure: Regenerate.
+
 2013-10-03  David Malcolm  <dmalcolm@redhat.com>
 
 	* configure.ac: Add --enable-host-shared.
diff --git a/libcpp/Makefile.in b/libcpp/Makefile.in
index 2353c9c043b..30bf8963cd8 100644
--- a/libcpp/Makefile.in
+++ b/libcpp/Makefile.in
@@ -57,6 +57,7 @@ CCDEPMODE = @CCDEPMODE@
 CXXDEPMODE = @CXXDEPMODE@
 DEPDIR = @DEPDIR@
 NOEXCEPTION_FLAGS = @noexception_flags@
+PICFLAG = @PICFLAG@
 
 datarootdir = @datarootdir@
 datadir = @datadir@
@@ -72,9 +73,9 @@ depcomp = $(SHELL) $(srcdir)/../depcomp
 INCLUDES = -I$(srcdir) -I. -I$(srcdir)/../include @INCINTL@ \
 	-I$(srcdir)/include
 
-ALL_CFLAGS = $(CFLAGS) $(WARN_CFLAGS) $(INCLUDES) $(CPPFLAGS)
+ALL_CFLAGS = $(CFLAGS) $(WARN_CFLAGS) $(INCLUDES) $(CPPFLAGS) $(PICFLAG)
 ALL_CXXFLAGS = $(CXXFLAGS) $(WARN_CXXFLAGS) $(NOEXCEPTION_FLAGS) $(INCLUDES) \
-	$(CPPFLAGS)
+	$(CPPFLAGS) $(PICFLAG)
 
 # The name of the compiler to use.
 COMPILER = $(CXX)
diff --git a/libcpp/configure b/libcpp/configure
index d2eaea05aeb..782a7105ac3 100755
--- a/libcpp/configure
+++ b/libcpp/configure
@@ -592,6 +592,7 @@ ac_includes_default="\
 #endif"
 
 ac_subst_vars='LTLIBOBJS
+PICFLAG
 MAINT
 USED_CATALOGS
 PACKAGE
@@ -7209,12 +7210,13 @@ esac
 # Enable --enable-host-shared.
 # Check whether --enable-host-shared was given.
 if test "${enable_host_shared+set}" = set; then :
-  enableval=$enable_host_shared; CFLAGS="-fPIC $CFLAGS"; CXXFLAGS="-fPIC $CXXFLAGS"
+  enableval=$enable_host_shared; PICFLAG=-fPIC
+else
+  PICFLAG=
 fi
 
 
 
-
 # Output.
 
 ac_config_headers="$ac_config_headers config.h:config.in"
diff --git a/libcpp/configure.ac b/libcpp/configure.ac
index 1b4920bb48a..a70603c95a6 100644
--- a/libcpp/configure.ac
+++ b/libcpp/configure.ac
@@ -224,9 +224,8 @@ esac
 AC_ARG_ENABLE(host-shared,
 [AS_HELP_STRING([--enable-host-shared],
 		[build host code as shared libraries])],
-[CFLAGS="-fPIC $CFLAGS"; CXXFLAGS="-fPIC $CXXFLAGS"], [])
-AC_SUBST(CFLAGS)
-AC_SUBST(CXXFLAGS)
+[PICFLAG=-fPIC], [PICFLAG=])
+AC_SUBST(PICFLAG)
 
 # Output.
 
diff --git a/libdecnumber/ChangeLog.jit b/libdecnumber/ChangeLog.jit
index fff6241658a..6f497d4888b 100644
--- a/libdecnumber/ChangeLog.jit
+++ b/libdecnumber/ChangeLog.jit
@@ -1,3 +1,11 @@
+2013-10-07  David Malcolm  <dmalcolm@redhat.com>
+
+	* Makefile.in: Set PICFLAG from configure script; add it to
+	ALL_CFLAGS.
+	* configure.ac (--enable-host-shared): Set up PICFLAG rather
+	than attempting to append -fPIC to CFLAGS, CXXFLAGS, LDFLAGS.
+	* configure: Regenerate.
+
 2013-10-03  David Malcolm  <dmalcolm@redhat.com>
 
 	* configure.ac: Add --enable-host-shared.
diff --git a/libdecnumber/Makefile.in b/libdecnumber/Makefile.in
index e67ff272f72..b6f3842b0d2 100644
--- a/libdecnumber/Makefile.in
+++ b/libdecnumber/Makefile.in
@@ -40,6 +40,7 @@ INSTALL_PROGRAM = @INSTALL_PROGRAM@
 LDFLAGS = @LDFLAGS@
 LIBICONV = @LIBICONV@
 PACKAGE = @PACKAGE@
+PICFLAG = @PICFLAG@
 RANLIB = @RANLIB@
 SHELL = @SHELL@
 objext = @OBJEXT@
@@ -57,7 +58,7 @@ enable_decimal_float= @enable_decimal_float@
 
 INCLUDES = -I$(srcdir) -I.
 
-ALL_CFLAGS = $(CFLAGS) $(WARN_CFLAGS) $(INCLUDES) $(CPPFLAGS)
+ALL_CFLAGS = $(CFLAGS) $(WARN_CFLAGS) $(INCLUDES) $(CPPFLAGS) $(PICFLAG)
 
 bid_OBJS = bid2dpd_dpd2bid.$(objext) host-ieee32.$(objext) \
 	host-ieee64.$(objext) host-ieee128.$(objext)
diff --git a/libdecnumber/configure b/libdecnumber/configure
index 61438ec148e..2720f46ff7f 100755
--- a/libdecnumber/configure
+++ b/libdecnumber/configure
@@ -593,7 +593,7 @@ ac_includes_default="\
 
 ac_subst_vars='LTLIBOBJS
 LIBOBJS
-CXXFLAGS
+PICFLAG
 ADDITIONAL_OBJS
 enable_decimal_float
 target_os
@@ -4895,12 +4895,13 @@ $as_echo "#define AC_APPLE_UNIVERSAL_BUILD 1" >>confdefs.h
 # Enable --enable-host-shared.
 # Check whether --enable-host-shared was given.
 if test "${enable_host_shared+set}" = set; then :
-  enableval=$enable_host_shared; CFLAGS="-fPIC $CFLAGS"; CXXFLAGS="-fPIC $CXXFLAGS"
+  enableval=$enable_host_shared; PICFLAG=-fPIC
+else
+  PICFLAG=
 fi
 
 
 
-
 # Output.
 
 ac_config_headers="$ac_config_headers config.h:config.in"
diff --git a/libdecnumber/configure.ac b/libdecnumber/configure.ac
index e2f0c92bf97..dd0499c43f6 100644
--- a/libdecnumber/configure.ac
+++ b/libdecnumber/configure.ac
@@ -99,9 +99,8 @@ AC_C_BIGENDIAN
 AC_ARG_ENABLE(host-shared,
 [AS_HELP_STRING([--enable-host-shared],
 		[build host code as shared libraries])],
-[CFLAGS="-fPIC $CFLAGS"; CXXFLAGS="-fPIC $CXXFLAGS"], [])
-AC_SUBST(CFLAGS)
-AC_SUBST(CXXFLAGS)
+[PICFLAG=-fPIC], [PICFLAG=])
+AC_SUBST(PICFLAG)
 
 # Output.
 
diff --git a/zlib/ChangeLog.jit b/zlib/ChangeLog.jit
index fff6241658a..0ffd0681896 100644
--- a/zlib/ChangeLog.jit
+++ b/zlib/ChangeLog.jit
@@ -1,3 +1,11 @@
+2013-10-07  David Malcolm  <dmalcolm@redhat.com>
+
+	* Makefile.am: Add PICFLAG to libz_a_CFLAGS.
+	* configure.ac (--enable-host-shared): Set up PICFLAG rather
+	than attempting to append -fPIC to CFLAGS.
+	* Makefile.in: Regenerate.
+	* configure: Regenerate.
+
 2013-10-03  David Malcolm  <dmalcolm@redhat.com>
 
 	* configure.ac: Add --enable-host-shared.
diff --git a/zlib/Makefile.am b/zlib/Makefile.am
index a9c42cb2cf5..82f709d9ec7 100644
--- a/zlib/Makefile.am
+++ b/zlib/Makefile.am
@@ -16,7 +16,7 @@ libzgcj_convenience_la_SOURCES = $(ZLIB_SOURCES)
 else
 toolexeclib_LIBRARIES = libz.a
 libz_a_SOURCES = $(ZLIB_SOURCES)
-libz_a_CFLAGS = $(AM_CFLAGS)
+libz_a_CFLAGS = $(AM_CFLAGS) $(PICFLAG)
 endif
 
 # Work around what appears to be a GNU make bug handling MAKEFLAGS
diff --git a/zlib/Makefile.in b/zlib/Makefile.in
index f5ef37a647f..3c8fd5978c8 100644
--- a/zlib/Makefile.in
+++ b/zlib/Makefile.in
@@ -177,6 +177,7 @@ PACKAGE_TARNAME = @PACKAGE_TARNAME@
 PACKAGE_URL = @PACKAGE_URL@
 PACKAGE_VERSION = @PACKAGE_VERSION@
 PATH_SEPARATOR = @PATH_SEPARATOR@
+PICFLAG = @PICFLAG@
 RANLIB = @RANLIB@
 SED = @SED@
 SET_MAKE = @SET_MAKE@
@@ -255,7 +256,7 @@ zconf.h.in zlib.h zutil.c zutil.h
 @TARGET_LIBRARY_TRUE@libzgcj_convenience_la_SOURCES = $(ZLIB_SOURCES)
 @TARGET_LIBRARY_FALSE@toolexeclib_LIBRARIES = libz.a
 @TARGET_LIBRARY_FALSE@libz_a_SOURCES = $(ZLIB_SOURCES)
-@TARGET_LIBRARY_FALSE@libz_a_CFLAGS = $(AM_CFLAGS)
+@TARGET_LIBRARY_FALSE@libz_a_CFLAGS = $(AM_CFLAGS) $(PICFLAG)
 
 # Work around what appears to be a GNU make bug handling MAKEFLAGS
 # values defined in terms of make variables, as is the case for CC and
diff --git a/zlib/configure b/zlib/configure
index 0edbe05fd83..32e33e7a6fa 100755
--- a/zlib/configure
+++ b/zlib/configure
@@ -602,6 +602,7 @@ ac_subst_vars='am__EXEEXT_FALSE
 am__EXEEXT_TRUE
 LTLIBOBJS
 LIBOBJS
+PICFLAG
 TARGET_LIBRARY_FALSE
 TARGET_LIBRARY_TRUE
 toolexeclibdir
@@ -10402,7 +10403,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 10405 "configure"
+#line 10406 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -10508,7 +10509,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 10511 "configure"
+#line 10512 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11206,10 +11207,13 @@ fi
 
 # Check whether --enable-host-shared was given.
 if test "${enable_host_shared+set}" = set; then :
-  enableval=$enable_host_shared; CFLAGS="-fPIC $CFLAGS"
+  enableval=$enable_host_shared; PICFLAG=-fPIC
+else
+  PICFLAG=
 fi
 
 
+
 ac_config_files="$ac_config_files Makefile"
 
 cat >confcache <<\_ACEOF
diff --git a/zlib/configure.ac b/zlib/configure.ac
index c2540d9aa03..fb8d943905e 100644
--- a/zlib/configure.ac
+++ b/zlib/configure.ac
@@ -122,7 +122,8 @@ fi
 AC_ARG_ENABLE(host-shared,
 [AS_HELP_STRING([--enable-host-shared],
 		[build host code as shared libraries])],
-[CFLAGS="-fPIC $CFLAGS"], [])
+[PICFLAG=-fPIC], [PICFLAG=])
+AC_SUBST(PICFLAG)
 
 AC_CONFIG_FILES([Makefile])
 AC_OUTPUT