[gcc r10-10781] configure: Allow host fragments to react to --enable-host-shared.

[Iain D Sandoe <iains@gcc.gnu.org>]

https://gcc.gnu.org/g:558cdc29cd614531d894f6368cad8cc95682793d

commit r10-10781-g558cdc29cd614531d894f6368cad8cc95682793d
Author: Iain Sandoe <iain@sandoe.co.uk>
Date:   Sat Aug 7 14:40:33 2021 +0100

    configure: Allow host fragments to react to --enable-host-shared.
    
    This makes the host_shared value available to host makefile
    fragments.
    
    It uses this to adjust Darwin's mdynamic-no-pic in the case that
    shared host resources are required.
    
    Signed-off-by: Iain Sandoe <iain@sandoe.co.uk>
    
    ChangeLog:
    
            * Makefile.in: Regenerate.
            * Makefile.tpl: Make the state of the configured host
            shared flag available to makefile fragements.
    
    config/ChangeLog:
    
            * mh-darwin: Require a non-shared host configuration to
            enable  mdynamic-no-pic where that is supported.
    
    (cherry picked from commit d39367fa82d95b646f0587a442156069100ee245)

Diff:
---
 Makefile.in      | 3 +++
 Makefile.tpl     | 3 +++
 config/mh-darwin | 8 ++++++++
 3 files changed, 14 insertions(+)

diff --git a/Makefile.in b/Makefile.in
index 36e369df6e7..b3b8485679c 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -109,6 +109,9 @@ RPATH_ENVVAR = @RPATH_ENVVAR@
 # executables in PATH.
 GCC_SHLIB_SUBDIR = @GCC_SHLIB_SUBDIR@
 
+# If the build should make suitable code for shared host resources.
+host_shared = @host_shared@
+
 # Build programs are put under this directory.
 BUILD_SUBDIR = @build_subdir@
 # This is set by the configure script to the arguments to use when configuring
diff --git a/Makefile.tpl b/Makefile.tpl
index efed1511750..a0ce803a0ad 100644
--- a/Makefile.tpl
+++ b/Makefile.tpl
@@ -112,6 +112,9 @@ RPATH_ENVVAR = @RPATH_ENVVAR@
 # executables in PATH.
 GCC_SHLIB_SUBDIR = @GCC_SHLIB_SUBDIR@
 
+# If the build should make suitable code for shared host resources.
+host_shared = @host_shared@
+
 # Build programs are put under this directory.
 BUILD_SUBDIR = @build_subdir@
 # This is set by the configure script to the arguments to use when configuring
diff --git a/config/mh-darwin b/config/mh-darwin
index fb2bb5ad1d9..b72835ae953 100644
--- a/config/mh-darwin
+++ b/config/mh-darwin
@@ -11,9 +11,15 @@
 # non-bootstrapped compiler), later stages will be built by GCC which supports
 # the required flags.
 
+# We cannot use mdynamic-no-pic when building shared host resources.
+
+ifeq (${host_shared},no)
 BOOTSTRAP_TOOL_CAN_USE_MDYNAMIC_NO_PIC := $(shell \
   $(CC) -S -xc /dev/null -o /dev/null -Werror -mno-dynamic-no-pic 2>/dev/null \
   && echo true)
+else
+BOOTSTRAP_TOOL_CAN_USE_MDYNAMIC_NO_PIC := false
+endif
 
 @if gcc-bootstrap
 ifeq (${BOOTSTRAP_TOOL_CAN_USE_MDYNAMIC_NO_PIC},true)
@@ -21,8 +27,10 @@ STAGE1_CFLAGS += -mdynamic-no-pic
 else
 STAGE1_CFLAGS += -fPIC
 endif
+ifeq (${host_shared},no)
 # Add -mdynamic-no-pic to later stages when we know it is built with GCC.
 BOOT_CFLAGS += -mdynamic-no-pic
+endif
 @endif gcc-bootstrap
 
 @unless gcc-bootstrap