From 5898417fddbf2b1386eab665d2a7a177d8073f4d Mon Sep 17 00:00:00 2001
From: Daiva Naudziuniene <daivan@fb.com>
Date: Fri, 9 Mar 2018 07:53:58 -0800
Subject: [PATCH] [frontend] Getting appropriate type information for exp in
 sizeof exp

Summary:
:
Previously, we did not have information about type of `exp` in `sizeof exp` from clang plugin which led to `Bad_footprint` errors. Infer did not understand `sizeof *p` in `struct Person* p = malloc(sizeof *p);` and used some default type.
This resulted in `Bad_footprint` error when trying to assign to a field `age` in `p->age=42;`.

This diff uses the version of clang plugin which exports the appropriate type information.

update-submodule: facebook-clang-plugins

Reviewed By: dulmarod

Differential Revision: D7179870

fbshipit-source-id: 4104f10
---
 facebook-clang-plugins                                    | 2 +-
 .../c/errors/null_dereference/null_pointer_dereference.c  | 8 ++++++++
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/facebook-clang-plugins b/facebook-clang-plugins
index 9d03cb460..a77526452 160000
--- a/facebook-clang-plugins
+++ b/facebook-clang-plugins
@@ -1 +1 @@
-Subproject commit 9d03cb460a30ad02d7b5edfa38f3a1143e642cfe
+Subproject commit a77526452b10339b3580d58b02c9c8f534b79589
diff --git a/infer/tests/codetoanalyze/c/errors/null_dereference/null_pointer_dereference.c b/infer/tests/codetoanalyze/c/errors/null_dereference/null_pointer_dereference.c
index ae03284a8..55678369f 100644
--- a/infer/tests/codetoanalyze/c/errors/null_dereference/null_pointer_dereference.c
+++ b/infer/tests/codetoanalyze/c/errors/null_dereference/null_pointer_dereference.c
@@ -129,3 +129,11 @@ void function_call_returns_allocated_pointer() {
   assign(p, 42);
   free(p);
 }
+
+void sizeof_expr_ok(void) {
+  struct Person* p = malloc(sizeof *p);
+  if (p) {
+    p->age = 42;
+  }
+  free(p);
+}