Merge branch 'em/missing-pager'

When a non-existent program is given as the pager, we tried to
reuse an uninitialized child_process structure and crashed, which
has been fixed.

* em/missing-pager:
  pager: fix crash when pager program doesn't exist

Author: gitster

pager.c

@@ -8,7 +8,7 @@
 #define DEFAULT_PAGER "less"
 #endif
 
-static struct child_process pager_process = CHILD_PROCESS_INIT;
+static struct child_process pager_process;
 static const char *pager_program;
 
 /* Is the value coming back from term_columns() just a guess? */
@@ -124,6 +124,8 @@ void setup_pager(void)
 
 	setenv("GIT_PAGER_IN_USE", "true", 1);
 
+	child_process_init(&pager_process);
+
 	/* spawn the pager */
 	prepare_pager_args(&pager_process, pager);
 	pager_process.in = -1;

t/t7006-pager.sh

@@ -760,4 +760,9 @@ test_expect_success TTY 'git returns SIGPIPE on propagated signals from pager' '
 	test_path_is_file pager-used
 '
 
+test_expect_success TTY 'non-existent pager doesnt cause crash' '
+	test_config pager.show invalid-pager &&
+	test_terminal git show
+'
+
 test_done