On 1/17/21 4:08 PM, H.J. Lu wrote:
On Sun, Jan 17, 2021 at 1:06 PM Tom Honermann via Gcc <gcc@gcc.gnu.org> wrote:
Hi all. I've been trying to build a custom gcc (trunk) with a custom
glibc (trunk) with support for C and C++ on x86_64 Linux and have so far
been unsuccessful at identifying a sequence of configure/make
invocations that completes successfully. I'm not trying to build a
cross compiler.
The scenario I'm trying to satisfy is testing some changes to gcc, and
additional changes to libstdc++ that have new autoconf and header
dependencies on the presence of new functions in existing glibc headers.
The glibc installation I'm trying to use was built with:
mkdir glibc-build
cd glibc-build
../glibc/configure \
CC=gcc \
CXX=g++ \
--prefix /.../glibc
make && make install
For gcc, I've tried numerous variants of the following:
mkdir gcc-build
cd gcc-build
../gcc/configure \
CC=gcc \
CXX=g++ \
--prefix /.../gcc \
--disable-multilib \
--enable-languages=c,c++ \
--enable-checking=release \
--disable-bootstrap \
--disable-lto
Things I've tried include setting CFLAGS, CXXFLAGS, and LDFLAGS to
specify additional glibc paths, to specify alternate paths (via
-nostdinc/-nostdinc++), setting LIBRARY_PATH and CPATH, passing
--with-sysroot, passing --with-headers and --with-libs, passing
--with-native-system-header-dir, some of those in conjunction with
removing --disable-bootstrap, and wrapping gcc in a script that attempts
to substitute certain include paths.
The problem I'm having is that, in every attempt, the glibc headers and
libraries from under /usr end up getting used instead of the custom
glibc ones at some point leading to build failures.
Does anyone have a recipe available for doing this?
Try scripts/build-many-glibcs.py in glibc source.
Thank you for the suggestion. I studied the script and tried using it,
but it also encountered errors during the 2nd stage gcc build. I didn't
delve into those errors.
This is what ended up working for me:
mkdir -p "$BINUTILS_BUILD_DIR"
cd "$BINUTILS_BUILD_DIR"
"../$BINUTILS_SOURCE_DIR/configure" \
CC=gcc \
CXX=g++ \
--prefix "$INSTALL_DIR" \
--with-sysroot="$INSTALL_DIR" \
--disable-multilib \
;
make -j 4 && make install
cd -
cd "$LINUX_SOURCE_DIR"
make INSTALL_HDR_PATH="$INSTALL_DIR" headers_install
cd -
mkdir -p "$GLIBC_BUILD_DIR"
cd "$GLIBC_BUILD_DIR"
"../$GLIBC_SOURCE_DIR/configure" \
CC=gcc \
CXX=g++ \
--prefix "$INSTALL_DIR" \
--disable-multilib \
--with-headers="$INSTALL_DIR/include" \
;
make -j 4 && make install
cd -
# Fixup paths in libc.so and libm.so. I wasn't able to find a
combination of
# 'configure --prefix' and 'make prefix=... DESTIDIR=...' that did
the right thing.
cp "$INSTALL_DIR/lib/libc.so" "$INSTALL_DIR/lib/libc.so.orig"
sed -e "s%$INSTALL_DIR%%g" "$INSTALL_DIR/lib/libc.so.orig" >
"$INSTALL_DIR/lib/libc.so"
rm -f "$INSTALL_DIR/lib/libc.so.orig"
cp "$INSTALL_DIR/lib/libm.so" "$INSTALL_DIR/lib/libm.so.orig"
sed -e "s%$INSTALL_DIR%%g" "$INSTALL_DIR/lib/libm.so.orig" >
"$INSTALL_DIR/lib/libm.so"
rm -f "$INSTALL_DIR/lib/libm.so.orig"
mkdir -p "$GCC_BUILD_DIR"
cd "$GCC_BUILD_DIR"
"../$GCC_SOURCE_DIR/configure" \
CC=gcc \
CXX=g++ \
--prefix "$INSTALL_DIR" \
--with-sysroot="$INSTALL_DIR" \
--with-native-system-header-dir="/include" \
--enable-languages=c,c++ \
--disable-bootstrap \
--disable-multilib \
--enable-checking=release \
--disable-lto \
;
make -j 4 && make install
cd -
Tom.
