This fixes PR61564 by diagnosing (and ignoring) options not marked with
'Optimization' being applied to #pragma GCC optimize or via the
optimize attribute.
The reason is that while we save/restore option state for 'Optimize'
marked options we don't do that for other options. Thus while such
options do not end up in the per-function optimize state applying them
still clobbers the global state.
Bootstrap and regtest running on x86_64-unknown-linux-gnu.
Ok for trunk?
Note this also points to the unfortunate ways the FEs apply
the pragma to functions which seems to be via adding optimize
attributes literally rather than copying a tree optimization
node constructable by parse_optimize_options. That results
in excessive diagnostics also reproducable without the patch
if you use sth like #pragma GCC optimize ("-Xhost").
Thanks,
Richard.
2016-06-07 Richard Biener <[email protected]>
PR c/61564
* c-common.c (parse_optimize_options): Only apply CL_OPTIMIZATION
options and warn about others.
* gcc.dg/Wpragmas-1.c: New testcase.
* gcc.dg/Wattributes-4.c: Likewise.
Index: gcc/c-family/c-common.c
===================================================================
*** gcc/c-family/c-common.c (revision 237167)
--- gcc/c-family/c-common.c (working copy)
*************** parse_optimize_options (tree args, bool
*** 9580,9585 ****
--- 9580,9608 ----
decode_cmdline_options_to_array_default_mask (opt_argc, opt_argv,
&decoded_options,
&decoded_options_count);
+ /* Drop non-Optimization options. */
+ unsigned j = 1;
+ for (i = 1; i < decoded_options_count; ++i)
+ {
+ if (! (cl_options[decoded_options[i].opt_index].flags &
CL_OPTIMIZATION))
+ {
+ ret = false;
+ if (attr_p)
+ warning (OPT_Wattributes,
+ "bad option %s to optimize attribute",
+ decoded_options[i].orig_option_with_args_text);
+ else
+ warning (OPT_Wpragmas,
+ "bad option %s to pragma attribute",
+ decoded_options[i].orig_option_with_args_text);
+ continue;
+ }
+ if (i != j)
+ decoded_options[j] = decoded_options[i];
+ j++;
+ }
+ decoded_options_count = j;
+ /* And apply them. */
decode_options (&global_options, &global_options_set,
decoded_options, decoded_options_count,
input_location, global_dc);
Index: gcc/testsuite/gcc.dg/Wpragmas-1.c
===================================================================
*** gcc/testsuite/gcc.dg/Wpragmas-1.c (revision 0)
--- gcc/testsuite/gcc.dg/Wpragmas-1.c (working copy)
***************
*** 0 ****
--- 1,11 ----
+ /* { dg-do compile } */
+
+ #pragma GCC push_options
+ #pragma GCC optimize ("-fno-lto") /* { dg-warning "bad option" } */
+ int main(void){return 0;}
+ #pragma GCC pop_options
+
+ /* ??? The FEs still apply the pragma string as optimize attribute to
+ all functions thus the diagnostic will be repeated for each function
+ affected. */
+ /* { dg-message "bad option" "" { target *-*-* } 0 } */
Index: gcc/testsuite/gcc.dg/Wattributes-4.c
===================================================================
*** gcc/testsuite/gcc.dg/Wattributes-4.c (revision 0)
--- gcc/testsuite/gcc.dg/Wattributes-4.c (working copy)
***************
*** 0 ****
--- 1,3 ----
+ /* { dg-do compile } */
+
+ int __attribute__((optimize("no-lto"))) main(void){return 0;} /* { dg-warning
"bad option" } */
