So the short story is that I'm stupid, but the long story is that I tried to
install Kerberos (manually) on my Gentoo box to help run something, but the
install didn't work.

Then, I realized I was an idiot, and the mit-krb5 is an emerge package. I
tried to delete all of the files associated with the install, and then I did
an "emerge mit-krb5".

I got the following:

In file included from krb5_libinit.c:5:
.../../include/krb5.h:2805: warning: "struct et_list" declared inside
parameter list
.../../include/krb5.h:2805: warning: its scope is only this definition
or declaration, which is probably not what you want
In file included from krb5_libinit.c:5:
.../../include/krb5.h:2852: warning: "struct et_list" declared inside
parameter list
In file included from krb5_libinit.c:5:
.../../include/krb5.h:2927: warning: "struct et_list" declared inside
parameter list
In file included from krb5_libinit.c:5:
.../../include/krb5.h:2954: warning: "struct et_list" declared inside
parameter list
In file included from krb5_libinit.c:5:
.../../include/krb5.h:2985: warning: "struct et_list" declared inside
parameter list
In file included from krb5_libinit.c:6:
.../../include/krb5_err.h:261: warning: "struct et_list" declared
inside parameter list
.../../include/krb5_err.h:261: error: conflicting types for
'initialize_krb5_error_table_r'
.../../include/krb5.h:2805: error: previous declaration of
'initialize_krb5_error_table_r' was here
.../../include/krb5_err.h:261: error: conflicting types for
'initialize_krb5_error_table_r'
.../../include/krb5.h:2805: error: previous declaration of
'initialize_krb5_error_table_r' was here
In file included from krb5_libinit.c:7:
.../../include/kv5m_err.h:69: warning: "struct et_list" declared inside
parameter list
.../../include/kv5m_err.h:69: error: conflicting types for
'initialize_kv5m_error_table_r'
.../../include/krb5.h:2927: error: previous declaration of
'initialize_kv5m_error_table_r' was here
.../../include/kv5m_err.h:69: error: conflicting types for
'initialize_kv5m_error_table_r'
.../../include/krb5.h:2927: error: previous declaration of
'initialize_kv5m_error_table_r' was here
In file included from krb5_libinit.c:8:
.../../include/asn1_err.h:25: warning: "struct et_list" declared inside
parameter list
.../../include/asn1_err.h:25: error: conflicting types for
'initialize_asn1_error_table_r'
.../../include/krb5.h:2985: error: previous declaration of
'initialize_asn1_error_table_r' was here
.../../include/asn1_err.h:25: error: conflicting types for
'initialize_asn1_error_table_r'
.../../include/krb5.h:2985: error: previous declaration of
'initialize_asn1_error_table_r' was here
In file included from krb5_libinit.c:9:
.../../include/kdb5_err.h:41: warning: "struct et_list" declared inside
parameter list
.../../include/kdb5_err.h:41: error: conflicting types for
'initialize_kdb5_error_table_r'
.../../include/krb5.h:2852: error: previous declaration of
'initialize_kdb5_error_table_r' was here
.../../include/kdb5_err.h:41: error: conflicting types for
'initialize_kdb5_error_table_r'
.../../include/krb5.h:2852: error: previous declaration of
'initialize_kdb5_error_table_r' was here
In file included from krb5_libinit.h:4,
from krb5_libinit.c:15:
.../../include/krb5.h:2805: warning: "struct et_list" declared inside
parameter list
.../../include/krb5.h:2805: error: conflicting types for
'initialize_krb5_error_table_r'

....and lots more similar errors.

What did I forget to remove? How do I fix this?

Thanks so much!!