You can call Carp's croak() from XS.

## test.pl ##
package MYFOO;
use warnings;
use Inline C => Config =>
    BUILD_NOISY => 1;

use Inline C => <<'EOC';

void foo() {
     croak("Package MYFOO, function foo() croaked");
}

EOC

MYFOO::foo(); #line 15

__END__
Outputs:

Package MYFOO, function foo() croaked at test.pl line 15.
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You can, but manually inserting that kind of info every time gets old. That's why it's worth the initial trouble to set it up so that contextual information gets inserted automatically.

package MyFoo;
use strict;
use warnings;
use Inline C => Config =>
    BUILD_NOISY => 1;

use Inline C => <<'EOC';

#line 9 "die_in_context.plx"
#define MY_PACKAGE "MyFoo"

#define kick_bucket(...) \
    do_kick_bucket(__FILE__, __LINE__, MY_PACKAGE, __func__, __VA_ARGS
+__)

void
do_kick_bucket(const char *file, I32 line, const char *package, 
               const char *func, const char *pat, ...) {
    va_list args;
    SV *error_sv = newSVpvn("", 0);

    va_start(args, pat);
    sv_vcatpvf(error_sv, pat, &args);
    va_end(args);

    sv_catpvf(error_sv, " at function %s::%s at %s line %d\n", 
            package, func, file, line);

    die(SvPVX(error_sv));
}

void 
foo() {
    kick_bucket("Bad Juju");
}

EOC

MyFoo::foo();

__END__
Outputs:

Bad Juju at function MyFoo::foo at die_in_context.plx line 30
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The package in XS functions you ordinarily get for free, because it's part of the function name and thus gets picked up by the __func__ macro. For example when I insert a call to my Confess macro into KinoSearch::Store::InStream::new, the stack trace starts like this...

Error in function XS_KinoSearch__Store__InStream_new at lib/KinoSearch
+.xs:1742: Kill me now
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__VA_ARGS__ and __func__ are C99, though, so if you need portability you have to probe for them at build time and set up alternatives for when they aren't available.

--
Marvin Humphrey
Rectangular Research ― http://www.rectangular.com

Here's code from KinoSearch::Util::Carp, which calls Carp::confess from C.

void Kino_confess (char* pat, ...) {
    va_list args;
    SV      *error_sv;

    dSP;

    error_sv = newSV(0);
    
    va_start(args, pat);
    sv_vsetpvf(error_sv, pat, &args);
    va_end(args);

    ENTER;
    SAVETMPS;
    PUSHMARK(SP);
    XPUSHs( sv_2mortal(error_sv) );
    PUTBACK;
    call_pv("Carp::confess", G_DISCARD);
    FREETMPS;
    LEAVE;
}
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It assumes that somewhere, someone has invoked use Carp;.

If you know that either ISO or GNU variadic macros are available, you can transparently insert the filename and the line number of the C file from where the exception was thrown, plus the function if either __func__ (C99) or __FUNCTION__ (GNU) is defined. Take a look at KinoSearch::Util::Carp in my svn repository if you want to see how that can work.

The bonus contextual info is just plain ol' nasty C wrangling though -- the XS-specific stuff is the same. Check out perlcall for more info on how to call back to Perl from C.