Fix false positive unsequenced access and modification warning in array subscript expression.
Summary: In the [expr.sub] p1, we can read that for a given E1[E2], E1 is sequenced before E2.
Patch by Mateusz Janek.
Reviewers: rsmith, Rakete1111
Reviewed By: rsmith, Rakete1111
Subscribers: riccibruno, lebedev.ri, Rakete1111, hiraditya, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D50766
llvm-svn: 350874
diff --git a/clang/test/SemaCXX/warn-unsequenced-cxx17.cpp b/clang/test/SemaCXX/warn-unsequenced-cxx17.cpp
new file mode 100644
index 0000000..3c221fb
--- /dev/null
+++ b/clang/test/SemaCXX/warn-unsequenced-cxx17.cpp
@@ -0,0 +1,8 @@
+// RUN: %clang_cc1 -fsyntax-only -verify -std=c++17 -Wno-unused %s
+
+void test() {
+ int xs[10];
+ int *p = xs;
+ // expected-no-diagnostics
+ p[(long long unsigned)(p = 0)]; // ok
+}
diff --git a/clang/test/SemaCXX/warn-unsequenced.cpp b/clang/test/SemaCXX/warn-unsequenced.cpp
index 9e8a5b4..6d4468c 100644
--- a/clang/test/SemaCXX/warn-unsequenced.cpp
+++ b/clang/test/SemaCXX/warn-unsequenced.cpp
@@ -81,6 +81,7 @@
int *p = xs;
a = *(a++, p); // ok
a = a++ && a; // ok
+ p[(long long unsigned)(p = 0)]; // expected-warning {{unsequenced modification and access to 'p'}}
A *q = &agg1;
(q = &agg2)->y = q->x; // expected-warning {{unsequenced modification and access to 'q'}}