SERVER-34396 Fail to compile if io manipulators like std::hex are passed to StringBuilder/str::stream

This includes a partial revert of 80f409d1311eb8d20251d17be474aff382538b84
(SERVER-34307) to address this bug.

3 files changed, 27 insertions, 11 deletions

diff --git a/src/mongo/bson/util/builder.h b/src/mongo/bson/util/builder.h
index f82ffccc3fa..ccf4cd183fd 100644
--- a/src/mongo/bson/util/builder.h
+++ b/src/mongo/bson/util/builder.h
@@ -455,6 +455,14 @@ public:
         return optional ? *this << *optional : *this << "(None)";
     }
 
+    /**
+     * Fail to compile if passed an unevaluated function, rather than allow it to decay and invoke
+     * the bool overload. This catches both passing std::hex (which isn't supported by this type)
+     * and forgetting to add () when doing `stream << someFuntion`.
+     */
+    template <typename R, typename... Args>
+    StringBuilderImpl& operator<<(R (*val)(Args...)) = delete;
+
     void appendDoubleNice(double x) {
         const int prev = _buf.l;
         const int maxSize = 32;
diff --git a/src/mongo/db/storage/mmap_v1/dur.cpp b/src/mongo/db/storage/mmap_v1/dur.cpp
index c8077f637d9..835f4302647 100644
--- a/src/mongo/db/storage/mmap_v1/dur.cpp
+++ b/src/mongo/db/storage/mmap_v1/dur.cpp
@@ -302,17 +302,17 @@ void debugValidateFileMapsMatch(const DurableMappedFile* mmf) {
         }
     }
 
-    invariant(
-        low == 0xffffffff,
-        str::stream() << "journal error warning views mismatch " << mmf->filename() << ' ' << hex
-                      << low
-                      << ".."
-                      << high
-                      << " len:"
-                      << high - low + 1
-                      << ". priv loc: "
-                      << (void*)(p + low)
-                      << ". Written data does not match in-memory view. Missing WriteIntent?");
+    if (low != 0xffffffff) {
+        std::stringstream ss;
+        ss << "journal error warning views mismatch " << mmf->filename() << ' ' << hex << low
+           << ".." << high << " len:" << high - low + 1;
+
+        log() << ss.str() << endl;
+        log() << "priv loc: " << (void*)(p + low) << ' ' << endl;
+
+        severe() << "Written data does not match in-memory view. Missing WriteIntent?";
+        MONGO_UNREACHABLE;
+    }
 }
 
 
diff --git a/src/mongo/util/mongoutils/str.h b/src/mongo/util/mongoutils/str.h
index c7fbdd724ba..6891d3f3008 100644
--- a/src/mongo/util/mongoutils/str.h
+++ b/src/mongo/util/mongoutils/str.h
@@ -72,6 +72,14 @@ public:
     operator mongo::StringData() const {
         return ss.stringData();
     }
+
+    /**
+     * Fail to compile if passed an unevaluated function, rather than allow it to decay and invoke
+     * the bool overload. This catches both passing std::hex (which isn't supported by this type)
+     * and forgetting to add () when doing `stream << someFuntion`.
+     */
+    template <typename R, typename... Args>
+    stream& operator<<(R (*val)(Args...)) = delete;
 };
 
 inline bool startsWith(const char* str, const char* prefix) {