[PATCH] fix uninitialized warnings

[Eric Wong <mwrap-perl@80x24.org>]

The `dump_fd' warning is legit but wasn't caught on my other system.
The `lineno' warning pops up on my system with `-O0'
---
 mwrap_core.h | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/mwrap_core.h b/mwrap_core.h
index 86e4498..a2c6d4a 100644
--- a/mwrap_core.h
+++ b/mwrap_core.h
@@ -388,9 +388,8 @@ static const COP *mwp_curcop(void)
 static const char *mw_perl_src_file_cstr(unsigned *lineno)
 {
 	const COP *cop = mwp_curcop();
-	if (!cop) return NULL;
-	*lineno = CopLINE(cop);
-	return CopFILE(cop);
+	*lineno = cop ? CopLINE(cop) : 0;
+	return cop ? CopFILE(cop) : NULL;
 }
 #	define SRC_FILE_CSTR(lineno) mw_perl_src_file_cstr(lineno)
 #endif /* MWRAP_PERL */
@@ -922,9 +921,13 @@ __attribute__ ((destructor)) static void mwrap_dtor(void)
 			fprintf(stderr, "open %s failed: %m\n", dump_path);
 			goto out;
 		}
-	} else if ((s = strstr(opt, "dump_fd:")) &&
-			!sscanf(s, "dump_fd:%d", &dump_fd))
-		goto out;
+	} else {
+		s = strstr(opt, "dump_fd:");
+		if (!s)
+			goto out;
+		if (!sscanf(s, "dump_fd:%d", &dump_fd))
+			goto out;
+	}
 
 	/* allow dump_csv standalone for dump_fd */
 	if (!a.dump_csv && strstr(opt, "dump_csv"))