[clang] [clang] fix wrong result of pointers comparison between unknown and stack (PR #122404)

[Balazs Benics via cfe-commits]

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@@ -0,0 +1,48 @@
+// RUN: %clang_analyze_cc1 -triple=x86_64-pc-linux-gnu -analyzer-checker=core,unix.Stream,debug.ExprInspection \
+// RUN:   -analyzer-config eagerly-assume=false,unix.Stream:Pedantic=true -verify %s
+// RUN: %clang_analyze_cc1 -triple=armv8-none-linux-eabi -analyzer-checker=core,unix.Stream,debug.ExprInspection \
+// RUN:   -analyzer-config eagerly-assume=false,unix.Stream:Pedantic=true -verify %s
+// RUN: %clang_analyze_cc1 -triple=aarch64-linux-gnu -analyzer-checker=core,unix.Stream,debug.ExprInspection \
+// RUN:   -analyzer-config eagerly-assume=false,unix.Stream:Pedantic=true -verify %s
+// RUN: %clang_analyze_cc1 -triple=hexagon -analyzer-checker=core,unix.Stream,debug.ExprInspection \
+// RUN:   -analyzer-config eagerly-assume=false,unix.Stream:Pedantic=true -verify %s
+
+#include "Inputs/system-header-simulator.h"
+
+char *get_str(char *Input);
+
+void check_f_leak() {
+  FILE *fp = fopen("test", "rb");
+  if (NULL == fp) {
+    return;
+  }
+  char str[64];
+  if (get_str(str) != str) {
+    fclose(fp);
+  }
+}// expected-warning {{Opened stream never closed. Potential resource leak}}
+
+void check_f_leak_2() {
+  FILE *fp = fopen("test", "rb");
+  if (NULL == fp) {
+    return;
+  }
+  char str[64];
+  if (get_str(str) != NULL) {
+    fclose(fp);
+  }
+}// expected-warning {{Opened stream never closed. Potential resource leak}}
+
+
+char *get_str_other(char *Input) {return Input;}
+
+void check_f_leak_3() {
+  FILE *fp = fopen("test", "rb");
+  if (NULL == fp) {
+    return;
+  }
+  char str[64];
+  if (get_str_other(str) != str) {
+    fclose(fp);
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steakhal wrote:

This is dead code.

https://github.com/llvm/llvm-project/pull/122404