substring_loc info needs default track-macro-expansion (PR preprocessor/78324)

gcc/ChangeLog:
	PR preprocessor/78324
	* input.c (get_substring_ranges_for_loc): Fail gracefully if
	-ftrack-macro-expansion has a value other than 2.

gcc/testsuite/ChangeLog:
	PR preprocessor/78324
	* gcc.dg/plugin/diagnostic-test-string-literals-1.c
	(test_multitoken_macro): New function.
	* gcc.dg/plugin/diagnostic-test-string-literals-3.c: New test
	case.
	* gcc.dg/plugin/diagnostic-test-string-literals-4.c: New test
	case.
	* gcc.dg/plugin/plugin.exp (plugin_test_list): Add the new test
	cases.
	* gcc.dg/tree-ssa/builtin-sprintf-warn-1.c (test_sprintf_note):
	Move to...
	* gcc.dg/tree-ssa/builtin-sprintf-warn-4.c: ...here.  Drop
	-ftrack-macro-expansion=0.
	(test_sprintf_note): Remove "P" macro.  Add
	dg-begin/end-multiline-output directives.
	(LINE, buffer, ptr): Copy from builtin-sprintf-warn-1.c.

From-SVN: r242667

1 files changed, 9 insertions, 0 deletions

diff --git a/gcc/input.c b/gcc/input.c
index 728f4dd..611e18b5 100644
--- a/gcc/input.c
+++ b/gcc/input.c
@@ -1322,6 +1322,15 @@ get_substring_ranges_for_loc (cpp_reader *pfile,
   if (strloc == UNKNOWN_LOCATION)
     return "unknown location";
 
+  /* Reparsing the strings requires accurate location information.
+     If -ftrack-macro-expansion has been overridden from its default
+     of 2, then we might have a location of a macro expansion point,
+     rather than the location of the literal itself.
+     Avoid this by requiring that we have full macro expansion tracking
+     for substring locations to be available.  */
+  if (cpp_get_options (pfile)->track_macro_expansion != 2)
+    return "track_macro_expansion != 2";
+
   /* If string concatenation has occurred at STRLOC, get the locations
      of all of the literal tokens making up the compound string.
      Otherwise, just use STRLOC.  */