[PATCH v2] driver: fix a problem with implementation of -falign-foo=0 [PR96247]

[Hu Jiangping]

Thanks, Richard!

I think your suggestion is very good, so I made a new patch.

v2: at a high level handles -falign-foo=0 like -falign-foo
v1: at the target level overides the -falign-foo=0 option values

Obviously, v2 is better than v1. In addition, anthor option
to reject 0 that discussed in the email and PR96247
is not as good as the current patch either, I think.

I tested this patch on x86_64, it works well. OK for trunk?

Regards!
Hujp

---
 gcc/opts.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/gcc/opts.c b/gcc/opts.c
index 499eb900643..ed6102cd606 100644
--- a/gcc/opts.c
+++ b/gcc/opts.c
@@ -2786,18 +2786,38 @@ common_handle_option (struct gcc_options *opts,
 
     case OPT_falign_loops_:
       check_alignment_argument (loc, arg, "loops");
+      // fix PR96247
+      if (0 == atoi(arg)) {
+        opts->x_flag_align_loops = true;
+        opts->x_str_align_loops = NULL;
+      }
       break;
 
     case OPT_falign_jumps_:
       check_alignment_argument (loc, arg, "jumps");
+      // fix PR96247
+      if (0 == atoi(arg)) {
+        opts->x_flag_align_jumps = true;
+        opts->x_str_align_jumps = NULL;
+      }
       break;
 
     case OPT_falign_labels_:
       check_alignment_argument (loc, arg, "labels");
+      // fix PR96247
+      if (0 == atoi(arg)) {
+        opts->x_flag_align_labels = true;
+        opts->x_str_align_labels = NULL;
+      }
       break;
 
     case OPT_falign_functions_:
       check_alignment_argument (loc, arg, "functions");
+      // fix PR96247
+      if (0 == atoi(arg)) {
+        opts->x_flag_align_functions = true;
+        opts->x_str_align_functions = NULL;
+      }
       break;
 
     case OPT_ftabstop_:
-- 
2.17.1