From: Iain Buclaw <ibuclaw@gdcproject.org>
Date: Sun, 11 Aug 2019 06:53:14 +0000 (+0000)
Subject: d: Fix ICE: gimplification failed (gimplify.c at 13436)
X-Git-Tag: misc/cutover-git~3560
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=4c9dbb967f3948630ae9cc79283c62e01399737f;p=thirdparty%2Fgcc.git

d: Fix ICE: gimplification failed (gimplify.c at 13436)

The expression that caused the ICE

	++(a += 1.0);

The D front-end rewrites and applies implicit type conversions so the
expression gets simplified as

	(int)((double) a += 1.0) += 1

The codegen pass would subsequently generate the following invalid code

	(int)(double) a = (int)((double) a + 1.0) + 1

The LHS expression `(int)(double) a', represented as a FIX_TRUNC_EXPR
being what trips as it is not a valid lvalue for assignment.

While LHS casts are stripped away, convert_expr adds a double cast
because it converts the expression to its original type before
converting it to its target type.  There is no valid reason why this is
done, so it has been removed.

gcc/d/ChangeLog:

	PR d/90601
	* d-convert.cc (convert_expr): Don't convert an expression to its
	original front-end type before converting to its target type.

gcc/testsuite/ChangeLog:

	PR d/90601
	* gdc.dg/pr90601.d: New test.

From-SVN: r274263
---

diff --git a/gcc/d/ChangeLog b/gcc/d/ChangeLog
index 04eaccf3fed5..5aa50a26ab50 100644
--- a/gcc/d/ChangeLog
+++ b/gcc/d/ChangeLog
@@ -1,3 +1,9 @@
+2019-08-11  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	PR d/90601
+	* d-convert.cc (convert_expr): Don't convert an expression to its
+	original front-end type before converting to its target type.
+
 2019-08-10  Iain Buclaw  <ibuclaw@gdcproject.org>
 
 	PR d/91238
diff --git a/gcc/d/d-convert.cc b/gcc/d/d-convert.cc
index b020eab902f8..fd4fc3c692db 100644
--- a/gcc/d/d-convert.cc
+++ b/gcc/d/d-convert.cc
@@ -588,7 +588,6 @@ convert_expr (tree exp, Type *etype, Type *totype)
 	  return compound_expr (exp, build_zero_cst (build_ctype (tbtype)));
 	}
 
-      exp = fold_convert (build_ctype (etype), exp);
       gcc_assert (TREE_CODE (exp) != STRING_CST);
       break;
     }
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index adf661130bc6..fdcb620c3be6 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2019-08-11  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	PR d/90601
+	* gdc.dg/pr90601.d: New test.
+
 2019-08-10  Steven G. Kargl  <kargl@gcc.gnu.org>
 
 	* gfortran.dg/boz_8.f90: Adjust error messages.
diff --git a/gcc/testsuite/gdc.dg/pr90601.d b/gcc/testsuite/gdc.dg/pr90601.d
new file mode 100644
index 000000000000..88cdaf8c99d0
--- /dev/null
+++ b/gcc/testsuite/gdc.dg/pr90601.d
@@ -0,0 +1,22 @@
+// https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90601
+// { dg-do compile }
+
+int postincr(int a)
+{
+    return (a += 1.0)++;
+}
+
+int postdecr(int a)
+{
+    return (a -= 1.0)--;
+}
+
+int preincr(int a)
+{
+    return ++(a += 1.0);
+}
+
+int predecr(int a)
+{
+    return --(a -= 1.0);
+}