diff --git a/Lib/platform.py b/Lib/platform.py
@@ -1198,7 +1198,9 @@ def _sys_version(sys_version=None):
        elif buildtime:
            builddate = builddate + ' ' + buildtime

-    if hasattr(sys, '_mercurial'):
        _, branch, revision = sys._mercurial
    elif hasattr(sys, 'subversion'):
        # sys.subversion was added in Python 2.5

diff --git a/Makefile.pre.in b/Makefile.pre.in
@@ -41,9 +41,9 @@ RANLIB=		@RANLIB@
READELF=	@READELF@
SOABI=		@SOABI@
LDVERSION=	@LDVERSION@
-HGVERSION=	@HGVERSION@
-HGTAG=		@HGTAG@
-HGBRANCH=	@HGBRANCH@
PGO_PROF_GEN_FLAG=@PGO_PROF_GEN_FLAG@
PGO_PROF_USE_FLAG=@PGO_PROF_USE_FLAG@
LLVM_PROF_MERGER=@LLVM_PROF_MERGER@
@@ -741,9 +741,9 @@ Modules/getbuildinfo.o: $(PARSER_OBJS) \
		$(MODOBJS) \
		$(srcdir)/Modules/getbuildinfo.c
	$(CC) -c $(PY_CORE_CFLAGS) \
-	      -DHGVERSION="\"`LC_ALL=C $(HGVERSION)`\"" \
-	      -DHGTAG="\"`LC_ALL=C $(HGTAG)`\"" \
-	      -DHGBRANCH="\"`LC_ALL=C $(HGBRANCH)`\"" \
	      -o $@ $(srcdir)/Modules/getbuildinfo.c

Modules/getpath.o: $(srcdir)/Modules/getpath.c Makefile

diff --git a/Misc/NEWS b/Misc/NEWS
@@ -806,6 +806,10 @@ Documentation
Build
-----

- bpo-29572: Update Windows build and OS X installers to use OpenSSL 1.0.2k.

- Issue #27659: Prohibit implicit C function declarations: use

diff --git a/Modules/getbuildinfo.c b/Modules/getbuildinfo.c
@@ -21,47 +21,47 @@
#endif

/* XXX Only unix build process has been tested */
-#ifndef HGVERSION
-#define HGVERSION ""
#endif
-#ifndef HGTAG
-#define HGTAG ""
#endif
-#ifndef HGBRANCH
-#define HGBRANCH ""
#endif

const char *
Py_GetBuildInfo(void)
{
-    static char buildinfo[50 + sizeof(HGVERSION) +
-                          ((sizeof(HGTAG) > sizeof(HGBRANCH)) ?
-                           sizeof(HGTAG) : sizeof(HGBRANCH))];
-    const char *revision = _Py_hgversion();
    const char *sep = *revision ? ":" : "";
-    const char *hgid = _Py_hgidentifier();
-    if (!(*hgid))
-        hgid = "default";
    PyOS_snprintf(buildinfo, sizeof(buildinfo),
-                  "%s%s%s, %.20s, %.9s", hgid, sep, revision,
                  DATE, TIME);
    return buildinfo;
}

const char *
-_Py_hgversion(void)
{
-    return HGVERSION;
}

const char *
-_Py_hgidentifier(void)
{
-    const char *hgtag, *hgid;
-    hgtag = HGTAG;
-    if ((*hgtag) && strcmp(hgtag, "tip") != 0)
-        hgid = hgtag;
    else
-        hgid = HGBRANCH;
-    return hgid;
}
diff --git a/Python/sysmodule.c b/Python/sysmodule.c
@@ -1960,9 +1960,9 @@ _PySys_Init(void)
                         PyUnicode_FromString(Py_GetVersion()));
    SET_SYS_FROM_STRING("hexversion",
                         PyLong_FromLong(PY_VERSION_HEX));
-    SET_SYS_FROM_STRING("_mercurial",
-                        Py_BuildValue("(szz)", "CPython", _Py_hgidentifier(),
-                                      _Py_hgversion()));
    SET_SYS_FROM_STRING("dont_write_bytecode",
                         PyBool_FromLong(Py_DontWriteBytecodeFlag));
    SET_SYS_FROM_STRING("api_version",

diff --git a/configure b/configure
@@ -760,10 +760,10 @@ build_os
build_vendor
build_cpu
build
-HAS_HG
-HGBRANCH
-HGTAG
-HGVERSION
BASECPPFLAGS
target_alias
host_alias
@@ -2698,17 +2698,17 @@ fi



-if test -e $srcdir/.hg/dirstate
then
-# Extract the first word of "hg", so it can be a program name with args.
-set dummy hg; ac_word=$2
{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_HAS_HG+:} false; then :
  $as_echo_n "(cached) " >&6
else
-  if test -n "$HAS_HG"; then
-  ac_cv_prog_HAS_HG="$HAS_HG" # Let the user override the test.
else
as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
for as_dir in $PATH
@@ -2717,39 +2717,39 @@ do
  test -z "$as_dir" && as_dir=.
    for ac_exec_ext in '' $ac_executable_extensions; do
  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
-    ac_cv_prog_HAS_HG="found"
    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
    break 2
  fi
done
  done
IFS=$as_save_IFS

-  test -z "$ac_cv_prog_HAS_HG" && ac_cv_prog_HAS_HG="not-found"
fi
fi
-HAS_HG=$ac_cv_prog_HAS_HG
-if test -n "$HAS_HG"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $HAS_HG" >&5
-$as_echo "$HAS_HG" >&6; }
else
  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
$as_echo "no" >&6; }
fi


else
-HAS_HG=no-repository
fi
-if test $HAS_HG = found
then
-    HGVERSION="hg id -i \$(srcdir)"
-    HGTAG="hg id -t \$(srcdir)"
-    HGBRANCH="hg id -b \$(srcdir)"
else
-    HGVERSION=""
-    HGTAG=""
-    HGBRANCH=""
fi
-Original file line number
+Diff line change
@@ Expand Up / @@ -806,6 +806,10 @@ Documentation @@
     Build
     -----
     - bpo-29572: Update Windows build and OS X installers to use OpenSSL 1.0.2k.
     - Issue #27659: Prohibit implicit C function declarations: use
@@ Expand Down @@