Changeset 8ac7bce6 for chapter06/gcc-pass2.xml

Timestamp:

03/03/2022 04:49:27 PM (2 years ago)

Author:

William Harrington <kb0iic@…>

Branches:

arm

Children:

9e1ce87

Parents:

b6d0e2b

git-author:

Xi Ruoyao <xry111@…> (03/01/2022 10:09:30 AM)

git-committer:

William Harrington <kb0iic@…> (03/03/2022 04:49:27 PM)

Message:

gcc-pass2: document *_FOR_TARGET parameters

File:

• chapter06/gcc-pass2.xml (modified) (2 diffs)

chapter06/gcc-pass2.xml

@@ -112 +112 @@
 
       <varlistentry>
-        <term><parameter>-with-build-sysroot=$LFS</parameter></term>
+        <term><parameter>--with-build-sysroot=$LFS</parameter></term>
         <listitem>
           <para>Normally, using <parameter>--host</parameter> ensures that
@@ -121 +121 @@
           needed to have them find the needed files in <filename
           class="directory">$LFS</filename>, and not on the host.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><parameter>--target=$LFS_TGT</parameter></term>
+        <listitem>
+          <para>As we are cross-compiling GCC, it's impossible to build
+          target libraries (<filename class="libraryfile">libgcc</filename>
+          and <filename class="libraryfile">libstdc++</filename>) with the
+          compiled GCC binaries because these binaries won't run on the
+          host distro.  GCC building system will attempt to use the
+          C and C++ compilers on the host distro as a workaround by default.
+          It's not supported to build GCC target libraries with a different
+          version of GCC, so using host compilers may cause building
+          failure.  This parameter ensures to build the libraries with GCC
+          pass 1 and prevent the issue.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><parameter>LDFLAGS_FOR_TARGET=...</parameter></term>
+        <listitem>
+          <para>Allow <filename class="libraryfile">libstdc++</filename> to
+          use shared <filename class="libraryfile">libgcc</filename> being
+          built in this pass, instead of the static version built in GCC
+          pass 1. This is needed for supporting C++ exception
+          handling.</para>
         </listitem>
       </varlistentry>