Find Possible Numerical Values of Enum Using GDB - enums

Question

With an enum declared and instantiated like this:
enum test_enumeration
{
test1 = 4,
test2 = 10,
test3,
};
test_enumeration test_enum;
I can call
(gdb) ptype test_enum
to get out
type = enum test_enumeration {test1 = 4, test2 = 10, test3}
This gives me the numerical value of test1 and test2 but NOT test3.
If I call
(gdb) print (int)test3
GDB prints out the value 11.
However I want to be able to get something like this:
type = enum test_enumeration {test1 = 4, test2 = 10, test3 = 11}
By printing out the entire type definition using test_enum.
Unfortunately
(gdb) ptype (int)test_enum
returns the the type as int and not the values.
Is there a way to print out the enum constants like this or an option that needs to be set to always display their numerical versions?
GDB V10.1

Answer 1

This will print out all the elements of an enum type. The executable needs to have been compiled with debuginfo.
$ cat print-enum.py
import gdb
class PrintEnumCmd(gdb.Command):
"""print all elements of the given enum type"""
def __init__(self):
super(PrintEnumCmd, self).__init__("print-enum", gdb.COMMAND_DATA, gdb.COMPLETE_EXPRESSION)
def invoke(self, argstr, from_tty):
typename = argstr
if not typename or typename.isspace():
raise gdb.GdbError("Usage: print-enum type")
try:
t = gdb.lookup_type(typename)
except gdb.error:
typename = "enum " + typename
try:
t = gdb.lookup_type(typename)
except gdb.error:
raise gdb.GdbError("type " + typename + " not found")
if t.code != gdb.TYPE_CODE_ENUM:
raise gdb.GdbError("type " + typename + " is not an enum")
for f in t.fields():
print(f.name, "=", f.enumval)
PrintEnumCmd()
$ gdb enu
Reading symbols from enu...done.
(gdb) source print-enum.py
(gdb) print-enum
Usage: print-enum type
(gdb) print-enum test<tab>
test1 test2 test3 test_enumeration
(gdb) print-enum test_enumeration
test1 = 4
test2 = 10
test3 = 11

Answer 2

This is not currently possible in GDB. The code that decides if the = VAL part should be printed is here:
https://sourceware.org/git/?p=binutils-gdb.git;a=blob;f=gdb/c-typeprint.c;h=0502d31eff9605e7e2e430c8ad72908792c1b475;hb=HEAD#l1607
The value is only printed if it is not 1 more than the value of the previous enum entry.