[clang] [StaticAnalyzer] early return if sym is concrete on assuming (PR #115579)

[Balazs Benics via cfe-commits]

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@@ -0,0 +1,33 @@
+// RUN: %clang_analyze_cc1 %s \
+// RUN:   -analyzer-checker=unix.StdCLibraryFunctions \
+// RUN:   -analyzer-config unix.StdCLibraryFunctions:ModelPOSIX=true \
+// RUN:   -analyzer-checker=debug.ExprInspection \
+// RUN:   -triple x86_64-unknown-linux-gnu \
+// RUN:   -verify
+
+// expected-no-diagnostics
+
+#include "Inputs/std-c-library-functions-POSIX.h"
+
+void _add_one_to_index_C(int *indices, int *shape) {
+  int k = 1;
+  for (; k >= 0; k--)
+    if (indices[k] < shape[k])
+      indices[k]++;
+    else
+      indices[k] = 0;
+}
+
+void PyObject_CopyData_sptr(char *i, char *j, int *indices, int itemsize,
+    int *shape, struct sockaddr *restrict sa) {
+  int elements = 1;
+  for (int k = 0; k < 2; k++)
+    elements += shape[k];
+
+  // no contradiction after 3 iterations when 'elements' could be
+  // simplified to 0
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steakhal wrote:

Can we dump some value to inspect that something got simplified here?
To me, having no reports in the test doesn't derive any information about what the test supposed to test.
By judging the file name, it crashed somewhere, but it's not clear at during which statement evaluation and in what constraints.

https://github.com/llvm/llvm-project/pull/115579