[PATCH] Require Python 3.4

[Tom Tromey <tromey@adacore.com>]

I believe we previously agreed that the minimum supported Python
version should be 3.4.  This patch makes this change, harmonizing the
documentation (which was inconsistent about the minimum version) and
the code.
---
 gdb/NEWS                     |  2 ++
 gdb/README                   |  2 +-
 gdb/configure                |  4 ++--
 gdb/configure.ac             |  4 ++--
 gdb/doc/gdb.texinfo          |  2 +-
 gdb/python/py-gdb-readline.c |  4 ----
 gdb/python/python-internal.h | 13 ++-----------
 7 files changed, 10 insertions(+), 21 deletions(-)

diff --git a/gdb/NEWS b/gdb/NEWS
index 42668cbc057..544e805915e 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -51,6 +51,8 @@
 
 * Python API
 
+  ** GDB no longer supports Python versions less than 3.4.
+
   ** Added gdb.record.clear.  Clears the trace data of the current recording.
      This forces re-decoding of the trace for successive commands.
 
diff --git a/gdb/README b/gdb/README
index d85c37d5d17..e3bfda45da1 100644
--- a/gdb/README
+++ b/gdb/README
@@ -516,7 +516,7 @@ more obscure GDB `configure' options are not listed here.
      GDB scripting much more powerful than the restricted CLI
      scripting language.  If your host does not have Python installed,
      you can find it on `http://www.python.org/download/'.  The oldest
-     version of Python supported by GDB is 3.2.  The optional argument
+     version of Python supported by GDB is 3.4.  The optional argument
      PYTHON is used to find the Python headers and libraries.  It can
      be either the name of a Python executable, or the name of the
      directory in which Python is installed.
diff --git a/gdb/configure b/gdb/configure
index ec9bbd3a842..e3e9d1c8ec7 100755
--- a/gdb/configure
+++ b/gdb/configure
@@ -28157,8 +28157,8 @@ int
 main ()
 {
 
-				    #if PY_MAJOR_VERSION != 3
-				    # error "We only support Python 3"
+				    #if PY_VERSION_HEX < 0x03040000
+				    # error "Minimum supported Python version is 3.4"
 				    #endif
 				    Py_Initialize ();
 
diff --git a/gdb/configure.ac b/gdb/configure.ac
index 21f5dc8dd30..250b014e56c 100644
--- a/gdb/configure.ac
+++ b/gdb/configure.ac
@@ -734,8 +734,8 @@ AC_DEFUN([AC_TRY_LIBPYTHON],
   found_usable_python=no
   AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include "Python.h"]],
                                  [[
-				    #if PY_MAJOR_VERSION != 3
-				    # error "We only support Python 3"
+				    #if PY_VERSION_HEX < 0x03040000
+				    # error "Minimum supported Python version is 3.4"
 				    #endif
 				    Py_Initialize ();
 				 ]])],
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index 554608da9fd..e12104867c4 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -41182,7 +41182,7 @@ libpython is present and found at configure time.)  Python makes
 @value{GDBN} scripting much more powerful than the restricted CLI
 scripting language.  If your host does not have Python installed, you
 can find it on @url{http://www.python.org/download/}.  The oldest version
-of Python supported by GDB is 3.0.1.  The optional argument @var{python}
+of Python supported by GDB is 3.4.  The optional argument @var{python}
 is used to find the Python headers and libraries.  It can be either
 the name of a Python executable, or the name of the directory in which
 Python is installed.
diff --git a/gdb/python/py-gdb-readline.c b/gdb/python/py-gdb-readline.c
index dd0ee45fe2e..d8782a9ff33 100644
--- a/gdb/python/py-gdb-readline.c
+++ b/gdb/python/py-gdb-readline.c
@@ -29,11 +29,7 @@
 
 static char *
 gdbpy_readline_wrapper (FILE *sys_stdin, FILE *sys_stdout,
-#if PY_MAJOR_VERSION == 3 && PY_MINOR_VERSION >= 4
 			const char *prompt)
-#else
-			char *prompt)
-#endif
 {
   int n;
   const char *p = NULL;
diff --git a/gdb/python/python-internal.h b/gdb/python/python-internal.h
index d723c4d577b..d3337de9043 100644
--- a/gdb/python/python-internal.h
+++ b/gdb/python/python-internal.h
@@ -87,6 +87,8 @@
 #include <frameobject.h>
 #include "py-ref.h"
 
+static_assert (PY_VERSION_HEX >= 0x03040000);
+
 #define Py_TPFLAGS_CHECKTYPES 0
 
 /* If Python.h does not define WITH_THREAD, then the various
@@ -134,17 +136,6 @@ typedef unsigned long gdb_py_ulongest;
 
 #endif /* HAVE_LONG_LONG */
 
-#if PY_VERSION_HEX < 0x03020000
-typedef long Py_hash_t;
-#endif
-
-/* PyMem_RawMalloc appeared in Python 3.4.  For earlier versions, we can just
-   fall back to PyMem_Malloc.  */
-
-#if PY_VERSION_HEX < 0x03040000
-#define PyMem_RawMalloc PyMem_Malloc
-#endif
-
 /* A template variable holding the format character (as for
    Py_BuildValue) for a given type.  */
 template<typename T>
-- 
2.47.0