diff --git a/src/libcmd/installables.cc b/src/libcmd/installables.cc index dca17555a..919db8c41 100644 --- a/src/libcmd/installables.cc +++ b/src/libcmd/installables.cc @@ -398,13 +398,10 @@ ref openEvalCache( EvalState & state, std::shared_ptr lockedFlake) { - auto fingerprint = lockedFlake->getFingerprint(); - return make_ref( - evalSettings.useEvalCache && evalSettings.pureEval - ? std::optional { std::cref(fingerprint) } - : std::nullopt, - state, - [&state, lockedFlake]() + auto fingerprint = evalSettings.useEvalCache && evalSettings.pureEval + ? std::make_optional(lockedFlake->getFingerprint()) + : std::nullopt; + auto rootLoader = [&state, lockedFlake]() { /* For testing whether the evaluation cache is complete. */ @@ -420,7 +417,17 @@ ref openEvalCache( assert(aOutputs); return aOutputs->value; - }); + }; + + if (fingerprint) { + auto search = state.evalCaches.find(fingerprint.value()); + if (search == state.evalCaches.end()) { + search = state.evalCaches.emplace(fingerprint.value(), make_ref(fingerprint, state, rootLoader)).first; + } + return search->second; + } else { + return make_ref(std::nullopt, state, rootLoader); + } } Installables SourceExprCommand::parseInstallables( diff --git a/src/libexpr/eval.hh b/src/libexpr/eval.hh index 2291d618c..69f56f6a8 100644 --- a/src/libexpr/eval.hh +++ b/src/libexpr/eval.hh @@ -32,6 +32,10 @@ class EvalState; class StorePath; struct SingleDerivedPath; enum RepairFlag : bool; +struct MemoryInputAccessor; +namespace eval_cache { + class EvalCache; +} /** @@ -233,6 +237,11 @@ public: return *new EvalErrorBuilder(*this, args...); } + /** + * A cache for evaluation caches, so as to reuse the same root value if possible + */ + std::map> evalCaches; + private: /* Cache for calls to addToStore(); maps source paths to the store