options: Adjust cl_optimization_compare to avoid checking ICE [PR115913]

At the end of a sequence like:
 #pragma GCC push_options
 ...
 #pragma GCC pop_options

the handler for pop_options calls cl_optimization_compare() (as generated by
optc-save-gen.awk) to make sure that all global state has been restored to
the value it had prior to the push_options call. The verification is
performed for almost all entries in the global_options struct. This leads to
unexpected checking asserts, as discussed in the PR, in case the state of
warnings-related options has been intentionally modified in between
push_options and pop_options via a call to #pragma GCC diagnostic. Address
that by skipping the verification for CL_WARNING-flagged options.

gcc/ChangeLog:

	PR middle-end/115913
	* optc-save-gen.awk (cl_optimization_compare): Skip options with
	CL_WARNING flag.

gcc/testsuite/ChangeLog:

	PR middle-end/115913
	* c-c++-common/cpp/pr115913.c: New test.

diff --git a/gcc/optc-save-gen.awk b/gcc/optc-save-gen.awk
index 76e9b3cb9402b27eb3babcd9696632ad41cb590d..dd09fd38c87b4b29f0f3b738601a69d5eb8ec293 100644 (file)
--- a/gcc/optc-save-gen.awk
+++ b/gcc/optc-save-gen.awk
@@ -1451,6 +1451,11 @@ for (i = 0; i < n_opts; i++) {
        if (name == "")
                continue;
 
+       # We do not want to compare warning-related options, since they
+       # might have been modified by a #pragma GCC diagnostic.
+       if (flag_set_p("Warning", flags[i]))
+               continue;
+
        if (name in checked_options)
                continue;
        checked_options[name]++

diff --git a/gcc/testsuite/c-c++-common/cpp/pr115913.c b/gcc/testsuite/c-c++-common/cpp/pr115913.c
new file mode 100644 (file)
index 0000000..b9d10cd
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/cpp/pr115913.c
@@ -0,0 +1,7 @@
+/* { dg-do preprocess } */
+/* PR middle-end/115913 */
+#pragma GCC push_options
+#pragma GCC diagnostic warning "-Wundef"
+/* The call to cl_optimization_compare performed by pop_options should not
+   lead to a checking failure.  */
+#pragma GCC pop_options