Fix potential use after free in tests

Signed-off-by: Stephan Krempel <krempel@par-tec.com>

Author: krempel-pt

test/test_common.h

@@ -99,11 +99,11 @@ extern FILE *file;
         char *fname = malloc(strlen(prefix) + MAX_DIGIT_LEN + 2);       \
         sprintf(fname, "%s.%d.%d", prefix, ns_id, rank);                \
         file = fopen(fname, "w");                                       \
-        free(fname);                                                    \
         if (NULL == file) {                                             \
             fprintf(stderr, "Cannot open file %s for writing!", fname); \
             exit(1);                                                    \
         }                                                               \
+        free(fname);                                                    \
     }
 
 #define TEST_CLOSE_FILE()     \

test/test_v2/test_common.h

@@ -127,11 +127,11 @@ extern FILE *pmixt_outfile;
     char *fname = malloc( strlen(prefix) + MAX_DIGIT_LEN + 2 ); \
     sprintf(fname, "%s.%d.%d", prefix, ns_id, rank); \
     pmixt_outfile = fopen(fname, "w"); \
-    free(fname); \
     if( NULL == pmixt_outfile ){ \
         fprintf(stderr, "Cannot open file %s for writing!", fname); \
         exit(1); \
     } \
+    free(fname); \
 }
 
 #define PMIXT_CLOSE_FILE() { \