Changeset 69a6e63c for chapter06/gcc-pass2.xml

Timestamp:

03/03/2022 04:36:02 PM (2 years ago)

Author:

William Harrington <kb0iic@…>

Branches:

arm

Children:

bd36dc5

Parents:

3ef45bc

git-author:

Xi Ruoyao <xry111@…> (02/26/2022 05:09:05 PM)

git-committer:

William Harrington <kb0iic@…> (03/03/2022 04:36:02 PM)

Message:

fix GCC PR100017 and enable libstdc++ for pass 2

This is the issue preventing us from cross-compiling libstdc++ in
Chapter 6. By fixing this issue we can remove a seperate pass 2 for
libstdc++ and simplify the instruction.

The upstream fix will be released in 11.3 and 12.0, so we can remove the
first sed upgrading gcc next time.

File:

• chapter06/gcc-pass2.xml (modified) (3 diffs)

chapter06/gcc-pass2.xml

@@ -68 +68 @@
 esac</userinput></screen>
 
+    <!-- https://gcc.gnu.org/PR100017 -->
+    <para>Fix an issue causing failure cross-compiling libstdc++:</para>
+
+<screen><userinput remap="pre">sed 's/gnu++17/&amp; -nostdinc++/' \
+    -i libstdc++-v3/src/c++17/Makefile.in</userinput></screen>
+
+    <para>Override the building rule of libgcc and libstdc++ headers, to
+    allow building these libraries with POSIX threads support:</para>
+
+<screen><userinput remap="pre">sed '/thread_header =/s/@.*@/gthr-posix.h/' \
+    -i libgcc/Makefile.in libstdc++-v3/include/Makefile.in</userinput></screen>
+
     <para>Create a separate build directory again:</para>
 
 <screen><userinput remap="pre">mkdir -v build
 cd       build</userinput></screen>
-
-    <para>Create a symlink that allows libgcc to be built with posix threads
-    support:</para>
-
-<screen><userinput remap="pre">mkdir -pv $LFS_TGT/libgcc
-ln -s ../../../libgcc/gthr-posix.h $LFS_TGT/libgcc/gthr-default.h</userinput></screen>
 
     <para>Before starting to build GCC, remember to unset any environment
@@ -89 +95 @@
     --prefix=/usr                                  \
     CC_FOR_TARGET=$LFS_TGT-gcc                     \
+    CXX_FOR_TARGET=$LFS_TGT-g++                    \
+    LDFLAGS_FOR_TARGET=-L$PWD/$LFS_TGT/libgcc      \
     --with-build-sysroot=$LFS                      \
     --enable-initfini-array                        \
@@ -99 +107 @@
     --disable-libssp                               \
     --disable-libvtv                               \
-    --disable-libstdcxx                            \
     --enable-languages=c,c++</userinput></screen>