https://gcc.gnu.org/g:2b37c9973967230b01dc5e38770fb3ec84610555
commit r13-9423-g2b37c9973967230b01dc5e38770fb3ec84610555
Author: Iain Buclaw <ibuc...@gdcproject.org>
Date: Tue Mar 11 17:56:18 2025 +0100
d: Fix regression returning from function with invariants [PR119139]
An optimization was added in GDC-12 which sets the TREE_READONLY flag on
all local variables with the storage class `const' assigned. For some
reason, const is also being added by the front-end to `__result'
variables in non-virtual functions, which ends up getting wrong code by
the gimplify pass promoting the local to static storage.
A bug has been raised upstream, as this looks like an error in the AST.
For now, turn off setting TREE_READONLY on all result variables.
PR d/119139
gcc/d/ChangeLog:
* decl.cc (get_symbol_decl): Don't set TREE_READONLY for __result
declarations.
gcc/testsuite/ChangeLog:
* gdc.dg/pr119139.d: New test.
(cherry picked from commit 81582ca6cb692098c1bda7995aec46c6cbfbfcb3)
Diff:
---
gcc/d/decl.cc | 2 +-
gcc/testsuite/gdc.dg/pr119139.d | 24 ++++++++++++++++++++++++
2 files changed, 25 insertions(+), 1 deletion(-)
diff --git a/gcc/d/decl.cc b/gcc/d/decl.cc
index 84274b3f3c31..deba3335a6a8 100644
--- a/gcc/d/decl.cc
+++ b/gcc/d/decl.cc
@@ -1313,7 +1313,7 @@ get_symbol_decl (Declaration *decl)
/* `const` applies to data that cannot be changed by the const reference
to that data. It may, however, be changed by another reference to that
same data. */
- if (vd->isConst () && !vd->isDataseg ())
+ if (vd->isConst () && !vd->isResult () && !vd->isDataseg ())
TREE_READONLY (decl->csym) = 1;
}
diff --git a/gcc/testsuite/gdc.dg/pr119139.d b/gcc/testsuite/gdc.dg/pr119139.d
new file mode 100644
index 000000000000..dc42c411e390
--- /dev/null
+++ b/gcc/testsuite/gdc.dg/pr119139.d
@@ -0,0 +1,24 @@
+// https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119139
+// { dg-do compile }
+// { dg-options "-fdump-tree-gimple" }
+string toString()
+{
+ return "1";
+}
+
+struct B
+{
+ ulong n;
+
+ invariant{}
+
+ string str()
+ {
+ if (n == 0)
+ {
+ return "0";
+ }
+ return toString();
+ }
+}
+// { dg-final { scan-tree-dump-not "static const struct __result =" "gimple"
} }
