[Bug target/63534] [5 Regression] Bootstrap failure on x86_64/i686-linux

["evstupac at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63534

Stupachenko Evgeny <evstupac at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |evstupac at gmail dot com

--- Comment #2 from Stupachenko Evgeny <evstupac at gmail dot com> ---
Before the changes there were potential bug as morestack call was emitted with
dependency on ebx (which was not set):

(call_insn 28 27 29 3 (call (mem:QI (symbol_ref:SI ("__morestack")) [0  S1 A8])
        (const_int 4 [0x4])) ../../../../gcc/libgo/runtime/go-assert.c:15 -1
     (nil) 
    (expr_list (use (reg:SI 3 bx))
        (nil))) 

Treating morestack as SYMBOL_FLAG_LOCAL resolves the issue.

The following patch should fix go bootstrap:
(bootstaped with --enable-languages=c,c++,fortran,lto,go)

diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index a3ca2ed..6235c4f 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -11999,7 +11999,10 @@ ix86_expand_split_stack_prologue (void)
                    REG_BR_PROB_BASE - REG_BR_PROB_BASE / 100);

   if (split_stack_fn == NULL_RTX)
-    split_stack_fn = gen_rtx_SYMBOL_REF (Pmode, "__morestack");
+    {
+      split_stack_fn = gen_rtx_SYMBOL_REF (Pmode, "__morestack");
+      SYMBOL_REF_FLAGS (split_stack_fn) |= SYMBOL_FLAG_LOCAL;
+    }
   fn = split_stack_fn;

   /* Get more stack space.  We pass in the desired stack space and the
@@ -12044,9 +12047,11 @@ ix86_expand_split_stack_prologue (void)
          gcc_assert ((args_size & 0xffffffff) == args_size);

          if (split_stack_fn_large == NULL_RTX)
-           split_stack_fn_large =
-             gen_rtx_SYMBOL_REF (Pmode, "__morestack_large_model");
-
+           {
+             split_stack_fn_large =
+               gen_rtx_SYMBOL_REF (Pmode, "__morestack_large_model");
+             SYMBOL_REF_FLAGS (split_stack_fn_large) |= SYMBOL_FLAG_LOCAL;
+           }
          if (ix86_cmodel == CM_LARGE_PIC)
            {
              rtx_code_label *label;