diff --git a/llvm/lib/Analysis/TargetLibraryInfo.cpp b/llvm/lib/Analysis/TargetLibraryInfo.cpp
index 8eb1a4929269d5..cfd9aff505620d 100644
--- a/llvm/lib/Analysis/TargetLibraryInfo.cpp
+++ b/llvm/lib/Analysis/TargetLibraryInfo.cpp
@@ -123,6 +123,7 @@ static void initialize(TargetLibraryInfoImpl &TLI, const Triple &T,
 
   // Set IO unlocked variants as unavailable
   // Set them as available per system below
+  TLI.setUnavailable(LibFunc_getc_unlocked);
   TLI.setUnavailable(LibFunc_getchar_unlocked);
   TLI.setUnavailable(LibFunc_putc_unlocked);
   TLI.setUnavailable(LibFunc_putchar_unlocked);
diff --git a/llvm/test/Transforms/InferFunctionAttrs/annotate.ll b/llvm/test/Transforms/InferFunctionAttrs/annotate.ll
index 31656e2bb2942d..80fb3ecf1bd6b7 100644
--- a/llvm/test/Transforms/InferFunctionAttrs/annotate.ll
+++ b/llvm/test/Transforms/InferFunctionAttrs/annotate.ll
@@ -509,7 +509,9 @@ declare i64 @fwrite(i8*, i64, i64, %opaque*)
 ; CHECK: declare noundef i32 @getc(%opaque* nocapture noundef) [[NOFREE_NOUNWIND]]
 declare i32 @getc(%opaque*)
 
-; CHECK: declare noundef i32 @getc_unlocked(%opaque* nocapture noundef) [[NOFREE_NOUNWIND]]
+; CHECK-KNOWN: declare noundef i32 @getc_unlocked(%opaque* nocapture noundef) [[NOFREE_NOUNWIND]]
+; CHECK-UNKNOWN: declare i32 @getc_unlocked(%opaque*)
+; CHECK-UNKNOWN-NOT: #{{.*}}
 declare i32 @getc_unlocked(%opaque*)
 
 ; CHECK: declare noundef i32 @getchar() [[NOFREE_NOUNWIND]]