From cfcbe45b607c1963e922fe869caf9b641855c695 Mon Sep 17 00:00:00 2001
From: Mayukha Vadari <mvadari@ripple.com>
Date: Tue, 6 Oct 2026 12:12:22 +0000
Subject: [PATCH] test: Declare, not define, entry instantiations in SLEBase
 test (#8357)

---
 src/tests/libxrpl/ledger/SLEBase.cpp | 27 +++++++++++++++++++--------
 1 file changed, 19 insertions(+), 8 deletions(-)

diff --git a/src/tests/libxrpl/ledger/SLEBase.cpp b/src/tests/libxrpl/ledger/SLEBase.cpp
index 231021aa12..17bf3afb8e 100644
--- a/src/tests/libxrpl/ledger/SLEBase.cpp
+++ b/src/tests/libxrpl/ledger/SLEBase.cpp
@@ -38,6 +38,7 @@
 #include <xrpl/ledger/entries/XChainOwnedClaimIDEntry.h>               // IWYU pragma: keep
 #include <xrpl/ledger/entries/XChainOwnedCreateAccountClaimIDEntry.h>  // IWYU pragma: keep
 #include <xrpl/protocol/Indexes.h>
+#include <xrpl/protocol/Keylet.h>
 #include <xrpl/protocol/LedgerFormats.h>
 #include <xrpl/protocol/SField.h>
 #include <xrpl/protocol/STLedgerEntry.h>
@@ -55,11 +56,11 @@
 
 namespace xrpl {
 
-// The entry classes have no consumers yet, and an un-instantiated class
-// template is barely type-checked. Instantiate every one explicitly so the
-// compiler actually checks them. Keep this block even once real call sites
-// exist: it is what catches a new ledger entry type being added without its
-// wrapper class, or the wrapper class existing but never actually being used.
+// An un-instantiated class template is barely type-checked. Name every entry
+// class in a static_assert below so its class definition is instantiated and
+// type-checked; the per-type suites check the member bodies. Keep this block
+// even once real call sites exist: it is what catches a new ledger entry type
+// being added without its wrapper class.
 //
 // Driving this off ledger_entries.macro keeps it exhaustive by construction:
 // adding a ledger entry type without adding its entry class stops compiling
@@ -76,12 +77,22 @@ template class SLEBase<ApplyView>;
 #pragma push_macro("LEDGER_ENTRY")
 #undef LEDGER_ENTRY
 
+// No explicit instantiation here, neither a definition nor a declaration.
+// A definition would instantiate an entry a second time once its member
+// bodies live in its own .cpp (MSVC rejects that with C4661 under /WX), and a
+// declaration (`extern template`) stops clang from emitting the inline
+// constructors of the header-only entries at -O0, which leaves them undefined
+// at link time in the debug builds. Naming the class in a static_assert is
+// enough to instantiate its definition, which is all this exhaustiveness
+// check needs; the per-type suites exercise the members.
 #define LEDGER_ENTRY(tag, value, name, ...)                                                    \
-    template class name##Entry<ReadView>;                                                      \
-    template class name##Entry<ApplyView>;                                                     \
     static_assert(                                                                             \
         name##Entry<ReadView>::kEntryType == tag && name##Entry<ApplyView>::kEntryType == tag, \
-        #name "Entry must be bound to " #tag);
+        #name "Entry must be bound to " #tag);                                                 \
+    static_assert(                                                                             \
+        std::is_constructible_v<name##Entry<ReadView>, Keylet const&, ReadView const&> &&      \
+            std::is_constructible_v<name##Entry<ApplyView>, Keylet const&, ApplyView&>,        \
+        #name "Entry must be constructible from a Keylet and a view");
 
 #include <xrpl/protocol/detail/ledger_entries.macro>