[gcc r13-7982] libstdc++: Build libstdc++_libbacktrace.a as PIC [PR111936]

[gcc r13-7982] libstdc++: Build libstdc++_libbacktrace.a as PIC [PR111936]

[Jonathan Wakely]

https://gcc.gnu.org/g:13ad7b1603f31b65e181780a29ada3f9a331bf8f

commit r13-7982-g13ad7b1603f31b65e181780a29ada3f9a331bf8f
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Tue Oct 24 16:56:30 2023 +0100

    libstdc++: Build libstdc++_libbacktrace.a as PIC [PR111936]
    
    In order for std::stacktrace to be used in a shared library, the
    libbacktrace symbols need to be built with -fPIC. Add the libtool
    -prefer-pic flag to the commands in src/libbacktrace/Makefile so that
    the archive contains PIC objects.
    
    libstdc++-v3/ChangeLog:
    
            PR libstdc++/111936
            * src/libbacktrace/Makefile.am: Add -prefer-pic to libtool
            compile commands.
            * src/libbacktrace/Makefile.in: Regenerate.
    
    (cherry picked from commit f32c1e1e96ffef6512ce025942b51f3967a3e7f2)

Diff:
---
 libstdc++-v3/src/libbacktrace/Makefile.am | 8 ++++++--
 libstdc++-v3/src/libbacktrace/Makefile.in | 7 ++++---
 2 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/libstdc++-v3/src/libbacktrace/Makefile.am b/libstdc++-v3/src/libbacktrace/Makefile.am
index 9abf9dd64a1a..998c059418eb 100644
--- a/libstdc++-v3/src/libbacktrace/Makefile.am
+++ b/libstdc++-v3/src/libbacktrace/Makefile.am
@@ -48,9 +48,13 @@ WARN_FLAGS = -W -Wall -Wwrite-strings -Wmissing-format-attribute \
 	     -Wcast-qual -Werror
 C_WARN_FLAGS = $(WARN_FLAGS) -Wstrict-prototypes -Wmissing-prototypes -Wold-style-definition -Wno-unused-but-set-variable
 CXX_WARN_FLAGS = $(WARN_FLAGS) -Wno-unused-parameter
-AM_CFLAGS = $(C_WARN_FLAGS)
+AM_CFLAGS = \
+	$(glibcxx_lt_pic_flag) $(glibcxx_compiler_shared_flag) \
+	$(C_WARN_FLAGS)
 AM_CFLAGS += $(EXTRA_CFLAGS)
-AM_CXXFLAGS = $(CXX_WARN_FLAGS) -fno-rtti -fno-exceptions
+AM_CXXFLAGS = \
+	$(glibcxx_lt_pic_flag) $(glibcxx_compiler_shared_flag) \
+	$(CXX_WARN_FLAGS) -fno-rtti -fno-exceptions
 AM_CXXFLAGS += $(EXTRA_CXXFLAGS)
 
 obj_prefix = std_stacktrace
diff --git a/libstdc++-v3/src/libbacktrace/Makefile.in b/libstdc++-v3/src/libbacktrace/Makefile.in
index 1c1242d88278..b5cce3741df3 100644
--- a/libstdc++-v3/src/libbacktrace/Makefile.in
+++ b/libstdc++-v3/src/libbacktrace/Makefile.in
@@ -498,9 +498,10 @@ libstdc___libbacktrace_la_CPPFLAGS = \
 
 C_WARN_FLAGS = $(WARN_FLAGS) -Wstrict-prototypes -Wmissing-prototypes -Wold-style-definition -Wno-unused-but-set-variable
 CXX_WARN_FLAGS = $(WARN_FLAGS) -Wno-unused-parameter
-AM_CFLAGS = $(C_WARN_FLAGS) $(EXTRA_CFLAGS)
-AM_CXXFLAGS = $(CXX_WARN_FLAGS) -fno-rtti -fno-exceptions \
-	$(EXTRA_CXXFLAGS)
+AM_CFLAGS = $(glibcxx_lt_pic_flag) $(glibcxx_compiler_shared_flag) \
+	$(C_WARN_FLAGS) $(EXTRA_CFLAGS)
+AM_CXXFLAGS = $(glibcxx_lt_pic_flag) $(glibcxx_compiler_shared_flag) \
+	$(CXX_WARN_FLAGS) -fno-rtti -fno-exceptions $(EXTRA_CXXFLAGS)
 obj_prefix = std_stacktrace
 
 # Each FILE.c in SOURCES will be compiled to SHORTNAME-FILE.o