i386: fix -march=amd crash

It started with g:3e2ae3ee285a57455d5a23bd352a68c289130186 where
new entry was added to processor_alias_table after generic node:

+  {"amdfam19h", PROCESSOR_GENERIC, CPU_GENERIC, 0,
+    M_CPU_TYPE (AMDFAM19H), P_NONE},

and then the following is violated:

/* NB: processor_alias_table stops at the "generic" entry.  */

gcc/ChangeLog:

	PR target/99753
	* common/config/i386/i386-common.c (ARRAY_SIZE): Fix off-by-one
	error.
	* config/i386/i386-options.c (ix86_option_override_internal):
	Add run-time assert.

gcc/testsuite/ChangeLog:

	PR target/99753
	* gcc.target/i386/pr99753.c: New test.

diff --git a/gcc/common/config/i386/i386-common.c b/gcc/common/config/i386/i386-common.c
index eea8af1..b89183b 100644 (file)
--- a/gcc/common/config/i386/i386-common.c
+++ b/gcc/common/config/i386/i386-common.c
@@ -2051,7 +2051,7 @@ const pta processor_alias_table[] =
 };
 
 /* NB: processor_alias_table stops at the "generic" entry.  */
-unsigned int const pta_size = ARRAY_SIZE (processor_alias_table) - 6;
+unsigned int const pta_size = ARRAY_SIZE (processor_alias_table) - 7;
 unsigned int const num_arch_names = ARRAY_SIZE (processor_alias_table);
 
 /* Provide valid option values for -march and -mtune options.  */

diff --git a/gcc/config/i386/i386-options.c b/gcc/config/i386/i386-options.c
index b653527..88d5e71 100644 (file)
--- a/gcc/config/i386/i386-options.c
+++ b/gcc/config/i386/i386-options.c
@@ -2042,6 +2042,9 @@ ix86_option_override_internal (bool main_args_p,
     sorry ("%i-bit mode not compiled in",
           (opts->x_ix86_isa_flags & OPTION_MASK_ISA_64BIT) ? 64 : 32);
 
+  /* Last processor_alias_table must point to "generic" entry.  */
+  gcc_checking_assert (strcmp (processor_alias_table[pta_size - 1].name,
+                              "generic") == 0);
   for (i = 0; i < pta_size; i++)
     if (! strcmp (opts->x_ix86_arch_string, processor_alias_table[i].name))
       {

diff --git a/gcc/testsuite/gcc.target/i386/pr99753.c b/gcc/testsuite/gcc.target/i386/pr99753.c
new file mode 100644 (file)
index 0000000..3def1fd
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr99753.c
@@ -0,0 +1,5 @@
+/* PR target/99753 */
+
+/* { dg-do compile } */
+/* { dg-options "-march=amd -m32" } */
+/* { dg-error "bad value .'amd'. for '-march=' switch"  "" { target *-*-* } 0 } */