configure: Fix uninitialized warnings in c-library.m4

Fixes for:
- PGAC_FUNC_GETTIMOFDAY_1ARG and
- PGAC_FUNC_GETPWUID_R_5ARG

config/c-library.m4

@@ -62,8 +62,8 @@ AC_DEFUN([PGAC_FUNC_GETTIMEOFDAY_1ARG],
 [AC_CACHE_CHECK(whether gettimeofday takes only one argument,
 pgac_cv_func_gettimeofday_1arg,
 [AC_TRY_COMPILE([#include <sys/time.h>],
-[struct timeval *tp;
-struct timezone *tzp;
+[struct timeval *tp = 0;
+struct timezone *tzp = 0;
 gettimeofday(tp,tzp);],
 [pgac_cv_func_gettimeofday_1arg=no],
 [pgac_cv_func_gettimeofday_1arg=yes])])
@@ -86,11 +86,11 @@ AC_DEFUN([PGAC_FUNC_GETPWUID_R_5ARG],
 pgac_cv_func_getpwuid_r_5arg,
 [AC_TRY_COMPILE([#include <sys/types.h>
 #include <pwd.h>],
-[uid_t uid;
-struct passwd *space;
-char *buf;
-size_t bufsize;
-struct passwd **result;
+[uid_t uid = 0;
+struct passwd *space = 0;
+char *buf = 0;
+size_t bufsize = 0;
+struct passwd **result = 0;
 getpwuid_r(uid, space, buf, bufsize, result);],
 [pgac_cv_func_getpwuid_r_5arg=yes],
 [pgac_cv_func_getpwuid_r_5arg=no])])

configure

@@ -14841,8 +14841,8 @@ else
 int
 main ()
 {
-struct timeval *tp;
-struct timezone *tzp;
+struct timeval *tp = 0;
+struct timezone *tzp = 0;
 gettimeofday(tp,tzp);
   ;
   return 0;
@@ -16362,11 +16362,11 @@ else
 int
 main ()
 {
-uid_t uid;
-struct passwd *space;
-char *buf;
-size_t bufsize;
-struct passwd **result;
+uid_t uid = 0;
+struct passwd *space = 0;
+char *buf = 0;
+size_t bufsize = 0;
+struct passwd **result = 0;
 getpwuid_r(uid, space, buf, bufsize, result);
   ;
   return 0;