Re: [PATCH] Objective-C: fix crash with -fobjc-nilcheck

[Matt Jacobson via Gcc-patches]

> On Aug 14, 2021, at 5:25 AM, Iain Sandoe <idsan...@googlemail.com> wrote:
> 
> 1/ please can you either post using a mailer that doesn’t mangle patches or 
> put the patch as a plain text attachment
>  (pushing to a git branch somewhere public also works for me, but maybe not 
> for all reviewers)
>   - for small patches like this I can obviously fix things up by hand, but 
> for anything larger not a good idea.
> 
> 2/ since this is fixing a crashing case, we should add a test to the test 
> suite for it (and also check the corresponding objective-c++).

Sorry for the broken patch.  I *think* this one should apply cleanly.  If not, 
I’ve also pushed the change to branch "objc-fix-struct-nil-check-10.3.0” of 
<g...@github.com:mhjacobson/gcc.git>, viewable at:

<https://github.com/mhjacobson/gcc/commit/5f158dc5f15fcbeae6163cc46cc520df8369681e>

I’ve also added a test specifically for this bug and in the process added 
-fobjc-nilcheck to the compiler invocation in objc-torture.exp.  Let me know 
what you think.

I’m not sure what you mean w.r.t. Objective-C++ -- can you explain?


gcc/testsuite/ChangeLog:

2021-08-14  Matt Jacobson  <mhjacob...@me.com>

        PR objc/101666
        * lib/objc-torture.exp: Test -fobjc-nilcheck when supported by target.
        * objc/compile/pr101666.m: New test.


gcc/objc/ChangeLog:

2021-08-14  Matt Jacobson  <mhjacob...@me.com>

        PR objc/101666
        * objc-next-runtime-abi-02.c (build_v2_objc_method_fixup_call): Fix 
crash.
        (build_v2_build_objc_method_call): Fix crash.


diff --git a/gcc/objc/objc-next-runtime-abi-02.c 
b/gcc/objc/objc-next-runtime-abi-02.c
index 66c13ad0db2..192731ff954 100644
--- a/gcc/objc/objc-next-runtime-abi-02.c
+++ b/gcc/objc/objc-next-runtime-abi-02.c
@@ -1676,11 +1676,7 @@ build_v2_objc_method_fixup_call (int super_flag, tree 
method_prototype,
       if (TREE_CODE (ret_type) == RECORD_TYPE
          || TREE_CODE (ret_type) == UNION_TYPE)
        {
-         vec<constructor_elt, va_gc> *rtt = NULL;
-         /* ??? CHECKME. hmmm..... think we need something more
-            here.  */
-         CONSTRUCTOR_APPEND_ELT (rtt, NULL_TREE, NULL_TREE);
-         ftree = objc_build_constructor (ret_type, rtt);
+         ftree = objc_build_constructor (ret_type, NULL);
        }
       else
        ftree = fold_convert (ret_type, integer_zero_node);
@@ -1790,11 +1786,7 @@ build_v2_build_objc_method_call (int super, tree 
method_prototype,
       if (TREE_CODE (ret_type) == RECORD_TYPE
          || TREE_CODE (ret_type) == UNION_TYPE)
        {
-         vec<constructor_elt, va_gc> *rtt = NULL;
-         /* ??? CHECKME. hmmm..... think we need something more
-            here.  */
-         CONSTRUCTOR_APPEND_ELT (rtt, NULL_TREE, NULL_TREE);
-         ftree = objc_build_constructor (ret_type, rtt);
+         ftree = objc_build_constructor (ret_type, NULL);
        }
       else
        ftree = fold_convert (ret_type, integer_zero_node);
diff --git a/gcc/testsuite/lib/objc-torture.exp 
b/gcc/testsuite/lib/objc-torture.exp
index 9aa5792f656..58c4b86f840 100644
--- a/gcc/testsuite/lib/objc-torture.exp
+++ b/gcc/testsuite/lib/objc-torture.exp
@@ -30,7 +30,11 @@ proc objc-set-runtime-options { dowhat args } {
     # that Darwin uses.  If NeXT is ported to another target, then it should
     # be listed here.
     if [istarget *-*-darwin*] {
-      lappend rtlist "-fnext-runtime" 
+      if { [istarget *64-*-*] || [istarget arm-*-*] } {
+       lappend rtlist "-fnext-runtime -fobjc-abi-version=2 -fobjc-nilcheck"
+      } else {
+       lappend rtlist "-fnext-runtime -fobjc-abi-version=1"
+      }
     }
     if [info exists OBJC_RUNTIME_OPTIONS] {
       foreach other $OBJC_RUNTIME_OPTIONS {
diff --git a/gcc/testsuite/objc/compile/pr101666.m 
b/gcc/testsuite/objc/compile/pr101666.m
new file mode 100644
index 00000000000..bfde52d3b35
--- /dev/null
+++ b/gcc/testsuite/objc/compile/pr101666.m
@@ -0,0 +1,15 @@
+struct point { double x, y, z; };
+
+@interface Foo
+
+- (struct point)bar;
+
+@end
+
+Foo *f;
+
+int
+main(void)
+{
+  struct point p = [f bar];
+}