Add back missing comments to build-essential chunk morphs

These will have been lost in the automated chunks-in-definitions
transition.

4 files changed, 44 insertions, 0 deletions

diff --git a/strata/armv7lhf-cross-toolchain/armv7lhf-cross-binutils.morph b/strata/armv7lhf-cross-toolchain/armv7lhf-cross-binutils.morph
index d92150a5..8e842e41 100644
--- a/strata/armv7lhf-cross-toolchain/armv7lhf-cross-binutils.morph
+++ b/strata/armv7lhf-cross-toolchain/armv7lhf-cross-binutils.morph
@@ -1,6 +1,7 @@
 name: armv7lhf-cross-binutils
 kind: chunk
 build-system: autotools
+
 configure-commands:
 - |
   # The TARGET used is the final triplet we expect, rather than that
diff --git a/strata/armv7lhf-cross-toolchain/armv7lhf-cross-eglibc.morph b/strata/armv7lhf-cross-toolchain/armv7lhf-cross-eglibc.morph
index afbfa939..ee28c9dd 100644
--- a/strata/armv7lhf-cross-toolchain/armv7lhf-cross-eglibc.morph
+++ b/strata/armv7lhf-cross-toolchain/armv7lhf-cross-eglibc.morph
@@ -1,8 +1,20 @@
 name: armv7lhf-cross-eglibc
 kind: chunk
+
 configure-commands:
 - mkdir o
+
+# Necessary for ARM port
 - cd libc && ln -s ../ports ports
+
+# Configure flag notes:
+#   1. Location of linux-api-headers, needed since eglibc doesn't
+#      support being given a sysroot.
+#   2. Location of binutils, since we build binutils for the final
+#      target triplet, but our gcc of our stage 1 target triplet.
+#   3. Normal flags. See eglibc.morph.
+#   4. Force configuration values of certain things that can't be detected
+#      in a cross-compile.
 - |
   export MORPH_ARCH=armv7lhf
   export TARGET=armv7lhf-baserock-linux-gnueabi
@@ -22,8 +34,10 @@ configure-commands:
             --enable-add-ons=nptl,ports --without-cvs --without-selinux \
     `# [4]` libc_cv_c_cleanup=yes libc_cv_ctors_header=yes \
             libc_cv_forced_unwind=yes libc_cv_ssp=no
+
 build-commands:
 - cd o && make localtime=UTC
+
 install-commands:
 - |
   # eglibc doesn't help with sysroots, so we need to spell out the
diff --git a/strata/armv7lhf-cross-toolchain/armv7lhf-cross-gcc-nolibc.morph b/strata/armv7lhf-cross-toolchain/armv7lhf-cross-gcc-nolibc.morph
index 9f993bc0..d164a60b 100644
--- a/strata/armv7lhf-cross-toolchain/armv7lhf-cross-gcc-nolibc.morph
+++ b/strata/armv7lhf-cross-toolchain/armv7lhf-cross-gcc-nolibc.morph
@@ -1,7 +1,20 @@
 name: armv7lhf-cross-gcc-nolibc
 kind: chunk
+
 configure-commands:
 - mkdir o
+
+# Configure flag notes:
+#  1. Standard flags. See gcc.morph.
+#  2. Our binutils is for the final $TARGET, rather than the intermediate
+#     target our GCC is being built for, so we need to set
+#     with-build-time-tools to get it to find our binutils at
+#     build-time and with-as and with-ld so our temporary GCC uses
+#     the appropriate tools when it compiles our libc, rather than
+#     trying to use $TARGET_STAGE1-as when producing binaries.
+#  3. Disable stuff that doesn't work when building a cross compiler
+#     without an existing libc, and generally try to keep this build as
+#     simple as possible.
 - |
   export MORPH_ARCH=armv7lhf
   export TARGET=armv7lhf-baserock-linux-gnueabi
@@ -25,10 +38,16 @@ configure-commands:
             --disable-shared --disable-threads --disable-target-libiberty \
             --disable-target-zlib --without-headers --with-newlib \
             --with-system-zlib
+
 build-commands:
 - cd o && make
+
 install-commands:
 - cd o && make DESTDIR="$DESTDIR" install
+
+# The file libgcc_eh is required during eglibc's build, but is not created
+# because we built GCC with --disable-shared. This is a workaround for
+# eglibc's build system being slightly broken.
 - |
   export TARGET_STAGE1=armv7lhf-none-linux-gnueabi
   libgcc_filename="$("$DESTDIR$PREFIX/bin/$TARGET_STAGE1-gcc" -print-libgcc-file-name)"
diff --git a/strata/armv7lhf-cross-toolchain/armv7lhf-cross-gcc.morph b/strata/armv7lhf-cross-toolchain/armv7lhf-cross-gcc.morph
index a5c6eac1..50c338e5 100644
--- a/strata/armv7lhf-cross-toolchain/armv7lhf-cross-gcc.morph
+++ b/strata/armv7lhf-cross-toolchain/armv7lhf-cross-gcc.morph
@@ -1,7 +1,15 @@
 name: armv7lhf-cross-gcc
 kind: chunk
+
 configure-commands:
 - mkdir o
+
+# Configure flag notes:
+#  1. Use the default sysroot path to install to and locate headers
+#  2. Recommended by Linux From Scratch; required for C++ ABI
+#     compatibility with other Linux distributions.
+#  3. Standard flags. See gcc.morph.
+#  4. Avoid having more than one copy of ZLib in use on the system
 - |
   export MORPH_ARCH=armv7lhf
   export TARGET=armv7lhf-baserock-linux-gnueabi
@@ -23,8 +31,10 @@ configure-commands:
             --with-mpfr-include="$(pwd)/../mpfr/src" \
             --with-mpfr-lib="$(pwd)/mpfr/src/.libs" \
     `# [4]` --with-system-zlib
+
 build-commands:
 - cd o && make
+
 install-commands:
 - cd o && make DESTDIR="$DESTDIR" install
 - |