diff --git a/clang/lib/StaticAnalyzer/Checkers/AssumeModeling.cpp b/clang/lib/StaticAnalyzer/Checkers/AssumeModeling.cpp
index 1e3adb4f266ca..789c7772d123a 100644
--- a/clang/lib/StaticAnalyzer/Checkers/AssumeModeling.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/AssumeModeling.cpp
@@ -45,7 +45,6 @@ void AssumeModelingChecker::checkPostStmt(const AttributedStmt *A,
       continue;
 
     const auto *Assumption = AssumptionVal.getAsInteger();
-    assert(Assumption && "We should know the exact outcome of an assume expr");
     if (Assumption && Assumption->isZero()) {
       C.addSink();
     }
diff --git a/clang/test/Analysis/cxx23-assume-attribute.cpp b/clang/test/Analysis/cxx23-assume-attribute.cpp
index 86e7662cd2af9..4cc16446572dc 100644
--- a/clang/test/Analysis/cxx23-assume-attribute.cpp
+++ b/clang/test/Analysis/cxx23-assume-attribute.cpp
@@ -69,3 +69,9 @@ int assume_and_fallthrough_at_the_same_attrstmt(int a, int b) {
 
   return 0;
 }
+
+void assume_opaque_gh151854_no_crash() {
+  extern bool opaque();
+  [[assume(opaque())]]; // no-crash
+  // expected-warning@-1 {{assumption is ignored because it contains (potential) side-effects}}
+}