gdb: Allow more control over where to find python libraries

The motivation behind this commit is to make it easier to bundle the
Python *.py library files with GDB when statically linking GDB against
libpython.  The Python files will be manually added into the GDB
installation tree, and GDB should be able to find them at run-time.
The installation tree will look like this:

  .
  |-- bin/
  |-- include/
  |-- lib/
  |   `-- python3.8/
  `-- share/

The benefit here is that the entire installation tree can be bundled
into a single archive and copied to another machine with a different
version of Python installed, and GDB will still work, including its
Python support.

In use the new configure options would be used something like this,
first build and install a static Python library:

  mkdir python
  cd python
  # Clone or download Python into a src/ directory.
  mkdir build
  export PYTHON_INSTALL_PATH=$PWD/install
  cd build
  ../src/configure --disable-shared --prefix=$PYTHON_INSTALL_PATH
  make
  make install

Now build and install GDB:

  mkdir binutils-gdb
  cd binutils-gdb
  # Clone or download GDB into a src/ directory.
  mkdir build
  export GDB_INSTALL_DIR=$PWD/install
  cd build
  ../src/configure \
      --prefix=$GDB_INSTALL_DIR \
      --with-python=$PYTHON_INSTALL_PATH/bin/python3 \
      --with-python-libdir=$GDB_INSTALL_DIR/lib
  make all-gdb
  make install-gdb

Finally, copy the Python libraries into the GDB install:

  cp -r $PYTHON_INSTALL_DIR/lib/python3.8/ $GDB_INSTALL_DIR/lib

After this the Python src, build, and install directories are no
longer needed and can be deleted.

If the new --with-python-libdir option is not used then the existing
behaviour is left unchanged, GDB will look for the Python libraries in
the lib/ directory within the python path.  The concatenation of the
python prefix and the string 'lib/' is now done at configure time,
rather than at run time in GDB as it was previous, however, this was
never something that the user had dynamic control over, so there's no
loss of functionality.

gdb/ChangeLog:

	* config.in: Regenerate.
	* configure: Regenerate.
	* configure.ac: Add --with-python-libdir option.
	* main.c: Use WITH_PYTHON_LIBDIR.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index e3f7e9f8288f2c9b440f207cc36da164cc68260f..405eecf79b085d37228597a27f411dda708d1f81 100644 (file)
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,10 @@
+2020-02-20  Andrew Burgess  <andrew.burgess@embecosm.com>
+
+       * config.in: Regenerate.
+       * configure: Regenerate.
+       * configure.ac: Add --with-python-libdir option.
+       * main.c: Use WITH_PYTHON_LIBDIR.
+
 2020-02-19  Tom Tromey  <tom@tromey.com>
 
        * symtab.c (general_symbol_info::compute_and_set_names): Use

diff --git a/gdb/config.in b/gdb/config.in
index cb886ba8e1a91890b4d8cda5d0fcd8d02a1ea77e..9c5c1ce834dbed189be88be5f3e11d886f3ee8d8 100644 (file)
--- a/gdb/config.in
+++ b/gdb/config.in
@@ -649,6 +649,10 @@
 /* Define as the return type of ptrace. */
 #undef PTRACE_TYPE_RET
 
+/* Define if the python lib directory should be relocated when GDB is moved.
+   */
+#undef PYTHON_LIBDIR_RELOCATABLE
+
 /* Define if the python directory should be relocated when GDB is moved. */
 #undef PYTHON_PATH_RELOCATABLE
 
@@ -752,6 +756,10 @@
 /* Define if the PPC simulator is being linked in. */
 #undef WITH_PPC_SIM
 
+/* Directory containing Python's standard libraries from --with-python-libdir.
+   */
+#undef WITH_PYTHON_LIBDIR
+
 /* Define if --with-python provides a path, either directly or via
    python-config.py --exec-prefix. */
 #undef WITH_PYTHON_PATH

diff --git a/gdb/configure b/gdb/configure
index 2f6ecb5c7a1179a112e5bfa7a5d9e5f29e03fae8..e6b5a510f6cec67bac744312d63308e179ea9afb 100755 (executable)
--- a/gdb/configure
+++ b/gdb/configure
@@ -890,6 +890,7 @@ with_mpfr
 with_libmpfr_prefix
 with_libmpfr_type
 with_python
+with_python_libdir
 with_guile
 enable_source_highlight
 with_intel_pt
@@ -1625,6 +1626,8 @@ Optional Packages:
   --with-libmpfr-type=TYPE     type of library to search for (auto/static/shared)
   --with-python[=PYTHON]  include python support
                           (auto/yes/no/<python-program>)
+  --with-python-libdir[=DIR]
+                          search for python's libraries in DIR
   --with-guile[=GUILE]    include guile support
                           (auto/yes/no/<guile-version>/<pkg-config-program>)
   --with-intel-pt         include Intel Processor Trace support (auto/yes/no)
@@ -10665,6 +10668,21 @@ _ACEOF
   fi
 fi
 
+
+# Check whether --with-python-libdir was given.
+if test "${with_python_libdir+set}" = set; then :
+  withval=$with_python_libdir;
+else
+
+    # If no python libdir is specified then select one based on
+    # python's prefix path.
+    if test -n "${python_prefix}"; then
+      with_python_libdir=${python_prefix}/lib
+    fi
+
+fi
+
+
 if test "${have_libpython}" != no; then
 
 $as_echo "#define HAVE_PYTHON 1" >>confdefs.h
@@ -10675,6 +10693,37 @@ $as_echo "#define HAVE_PYTHON 1" >>confdefs.h
   CONFIG_INSTALL="$CONFIG_INSTALL install-python"
   ENABLE_CFLAGS="$ENABLE_CFLAGS \$(SUBDIR_PYTHON_CFLAGS)"
 
+  if test -n "${with_python_libdir}"; then
+
+cat >>confdefs.h <<_ACEOF
+#define WITH_PYTHON_LIBDIR "${with_python_libdir}"
+_ACEOF
+
+
+  if test "x$exec_prefix" = xNONE || test "x$exec_prefix" = 'x${prefix}'; then
+     if test "x$prefix" = xNONE; then
+       test_prefix=/usr/local
+     else
+       test_prefix=$prefix
+     fi
+  else
+     test_prefix=$exec_prefix
+  fi
+  value=0
+  case ${with_python_libdir} in
+     "${test_prefix}"|"${test_prefix}/"*|\
+       '${exec_prefix}'|'${exec_prefix}/'*)
+     value=1
+     ;;
+  esac
+
+cat >>confdefs.h <<_ACEOF
+#define PYTHON_LIBDIR_RELOCATABLE $value
+_ACEOF
+
+
+  fi
+
   # Flags needed to compile Python code (taken from python-config --cflags).
   # We cannot call python-config directly because it will output whatever was
   # used when compiling the Python interpreter itself, including flags which

diff --git a/gdb/configure.ac b/gdb/configure.ac
index 335971fdf669ff4a6911edf501f648a75ce1d4a6..a51c5eda6b59b33a9aa389d1416e12eb9e2264bd 100644 (file)
--- a/gdb/configure.ac
+++ b/gdb/configure.ac
@@ -890,6 +890,24 @@ else
   fi
 fi
 
+dnl Use --with-python-libdir to control where GDB looks for the Python
+dnl libraries.
+dnl
+dnl If this is not given then the default will be based on the value
+dnl passed to --with-python, which is in the python_prefix variable.
+dnl If the --with-python option wasn't given then the default value in
+dnl python_prefix is based on running the 'gdb/python/python-config
+dnl --exec-prefix' script.
+AC_ARG_WITH(python-libdir,
+  AS_HELP_STRING([--with-python-libdir@<:@=DIR@:>@], [search for python's libraries in DIR]),
+  [],[
+    # If no python libdir is specified then select one based on
+    # python's prefix path.
+    if test -n "${python_prefix}"; then
+      with_python_libdir=${python_prefix}/lib
+    fi
+  ])
+
 if test "${have_libpython}" != no; then
   AC_DEFINE(HAVE_PYTHON, 1, [Define if Python interpreter is being linked in.])
   CONFIG_OBS="$CONFIG_OBS \$(SUBDIR_PYTHON_OBS)"
@@ -898,6 +916,12 @@ if test "${have_libpython}" != no; then
   CONFIG_INSTALL="$CONFIG_INSTALL install-python"
   ENABLE_CFLAGS="$ENABLE_CFLAGS \$(SUBDIR_PYTHON_CFLAGS)"
 
+  if test -n "${with_python_libdir}"; then
+    AC_DEFINE_UNQUOTED(WITH_PYTHON_LIBDIR, "${with_python_libdir}",
+                      [Directory containing Python's standard libraries from --with-python-libdir.])
+    GDB_AC_DEFINE_RELOCATABLE(PYTHON_LIBDIR, [python lib], ${with_python_libdir})
+  fi
+
   # Flags needed to compile Python code (taken from python-config --cflags).
   # We cannot call python-config directly because it will output whatever was
   # used when compiling the Python interpreter itself, including flags which

diff --git a/gdb/main.c b/gdb/main.c
index d5e5a678baa729d7b9210fecf9ef650f5c5233e9..a03ed8117ab6daca61c300b9031714102e86447b 100644 (file)
--- a/gdb/main.c
+++ b/gdb/main.c
@@ -575,14 +575,9 @@ captured_main_1 (struct captured_main_args *context)
   gdb_datadir = relocate_gdb_directory (GDB_DATADIR,
                                        GDB_DATADIR_RELOCATABLE);
 
-#ifdef WITH_PYTHON_PATH
-  {
-    /* For later use in helping Python find itself.  */
-    char *tmp = concat (WITH_PYTHON_PATH, SLASH_STRING, "lib", (char *) NULL);
-
-    python_libdir = relocate_gdb_directory (tmp, PYTHON_PATH_RELOCATABLE);
-    xfree (tmp);
-  }
+#ifdef WITH_PYTHON_LIBDIR
+  python_libdir = relocate_gdb_directory (WITH_PYTHON_LIBDIR,
+                                         PYTHON_LIBDIR_RELOCATABLE);
 #endif
 
 #ifdef RELOC_SRCDIR