preprocessor: Create the parser before handling command-line includes [PR115312]

Since r14-2893, we create a parser object in preprocess-only mode for the
purpose of parsing #pragma while preprocessing. The parser object was
formerly created after calling c_finish_options(), which leads to problems
on platforms that don't use stdc-predef.h (such as MinGW, as reported in
the PR). On such platforms, the call to c_finish_options() will process
the first command-line-specified include file. If that includes a PCH, then
c-ppoutput.cc will encounter a state it did not anticipate. Fix it by
creating the parser prior to calling c_finish_options().

gcc/c-family/ChangeLog:

	PR pch/115312
	* c-opts.cc (c_common_init): Call c_init_preprocess() before
	c_finish_options() so that a parser is available to process any
	includes specified on the command line.

gcc/testsuite/ChangeLog:

	PR pch/115312
	* g++.dg/pch/pr115312.C: New test.
	* g++.dg/pch/pr115312.Hs: New test.

diff --git a/gcc/c-family/c-opts.cc b/gcc/c-family/c-opts.cc
index 33114f13c8dbd3d9e2cfdb2b90f289dbb275658f..b7789b707e63ac44b28aa5a061c433bdd0360ef9 100644 (file)
--- a/gcc/c-family/c-opts.cc
+++ b/gcc/c-family/c-opts.cc
@@ -1296,8 +1296,8 @@ c_common_init (void)
 
   if (flag_preprocess_only)
     {
-      c_finish_options ();
       c_init_preprocess ();
+      c_finish_options ();
       preprocess_file (parse_in);
       return false;
     }

diff --git a/gcc/testsuite/g++.dg/pch/pr115312.C b/gcc/testsuite/g++.dg/pch/pr115312.C
new file mode 100644 (file)
index 0000000..9074ad4
--- /dev/null
+++ b/gcc/testsuite/g++.dg/pch/pr115312.C
@@ -0,0 +1,2 @@
+/* { dg-additional-options "-include pr115312.H -save-temps" } */
+#error "suppress PCH assembly comparison, which does not work with -save-temps" /* { dg-error "." } */

diff --git a/gcc/testsuite/g++.dg/pch/pr115312.Hs b/gcc/testsuite/g++.dg/pch/pr115312.Hs
new file mode 100644 (file)
index 0000000..6e7c6bc
--- /dev/null
+++ b/gcc/testsuite/g++.dg/pch/pr115312.Hs
@@ -0,0 +1 @@
+// This space intentionally left blank.