Cannot enter floating point (double) numbers

After further investigation it seems that gdb assumes that floating-point numbers use . as decimal mark, as these lines from c-exp.y show

            else if (!got_dot && *p == '.')
              got_dot = 1;

but, later, the function parse_float() (in parse.c) feeds the string into sscanf

  num = sscanf (copy, "%" DOUBLEST_SCAN_FORMAT "%n", d, &n);

and, apparently, sscanf is locale-sensitive, so, if the current locale has , as decimal mark, sscanf will leave everything past the . sign unscanned. gdb, then, notices that something is unscanned and says "invalid number"

Filed upstream bug https://sourceware.org/bugzilla/show_bug.cgi?id=17607

this works for me in 14.10

Sorry, but I can still reproduce it.

Precondition is that gdb is built with Python 3 support (and the one distributed with Ubuntu 14.10 is) and the current locale has a comma as decimal separator (I am using it_IT.UTF-8).

At startup, gdb executes _initialize_python () (in file python/python.c): the following lines of code changhe the locale from C (which is the appropriate one, since gdb must be able to parse numbers that are valid in C language) to the one of the machine

1651 progname = concat (ldirname (python_libdir), SLASH_STRING, "bin",
1652 SLASH_STRING, "python", NULL);
1653 #ifdef IS_PY3K
1654 oldloc = setlocale (LC_ALL, NULL);
1655 setlocale (LC_ALL, "");

From this point on, gdb assumes that the decimal separator is a comma, and becomes unable to parse the number 1.0

It works correctly if started as

LC_NUMERIC=C gdb

to force the correct locale