Remove frameptr-based unwinder.

The frameptr-based unwinder was an interim solution while issues with
libunwind were resolved. It's better if we remove it,
so we don't have to support it moving forward.

configure.ac

@@ -1557,33 +1557,6 @@ if test "x$backtrace_method" = "x" -a "x$enable_prof_libunwind" = "x1" ; then
   fi
 fi
 
-if test `uname -s` = "Linux"
-then
-  AC_ARG_ENABLE([prof-frameptr],
-    [AS_HELP_STRING([--enable-prof-frameptr], [Use optimized frame pointer unwinder for backtracing (Linux only)])],
-  [if test "x$enable_prof_frameptr" = "xno" ; then
-    enable_prof_frameptr="0"
-  else
-    enable_prof_frameptr="1"
-    if test "x$enable_prof" = "x0" ; then
-      AC_MSG_ERROR([--enable-prof-frameptr should only be used with --enable-prof])
-    fi
-  fi
-  ],
-  [enable_prof_frameptr="0"]
-  )
-  if test "x$backtrace_method" = "x" -a "x$enable_prof_frameptr" = "x1" \
-      -a "x$GCC" = "xyes" ; then
-    JE_CFLAGS_ADD([-fno-omit-frame-pointer])
-    backtrace_method="frame pointer linux"
-    AC_DEFINE([JEMALLOC_PROF_FRAME_POINTER], [ ], [ ])
-  else
-    enable_prof_frameptr="0"
-  fi
-else
-  enable_prof_frameptr="0"
-fi
-
 AC_ARG_ENABLE([prof-libgcc],
   [AS_HELP_STRING([--disable-prof-libgcc],
   [Do not use libgcc for backtracing])],
@@ -3186,7 +3159,6 @@ AC_MSG_RESULT([user_config        : ${enable_user_config}])
 AC_MSG_RESULT([experimental_smallocx : ${enable_experimental_smallocx}])
 AC_MSG_RESULT([prof               : ${enable_prof}])
 AC_MSG_RESULT([prof-libunwind     : ${enable_prof_libunwind}])
-AC_MSG_RESULT([prof-frameptr      : ${enable_prof_frameptr}])
 AC_MSG_RESULT([prof-libgcc        : ${enable_prof_libgcc}])
 AC_MSG_RESULT([prof-gcc           : ${enable_prof_gcc}])
 AC_MSG_RESULT([fill               : ${enable_fill}])