Revert "Don't anticipate CA but not fixed outputs for now"

This reverts commit 3a9e4c3.

src/libstore/build.cc

@@ -3721,9 +3721,22 @@ void DerivationGoal::registerOutputs()
  hash). */
  std::optional<ContentAddress> ca;
 
- if (derivationIsFixed(derivationType)) {
-
- FixedOutputHash outputHash = std::get<DerivationOutputFixed>(i.second.output).hash;
+ if (! std::holds_alternative<DerivationOutputInputAddressed>(i.second.output)) {
+ DerivationOutputFloating outputHash;
+ std::visit(overloaded {
+ [&](DerivationOutputInputAddressed doi) {
+ throw Error("No.");
+ },
+ [&](DerivationOutputFixed dof) {
+ outputHash = DerivationOutputFloating {
+ .method = dof.hash.method,
+ .hashType = *dof.hash.hash.type,
+ };
+ },
+ [&](DerivationOutputFloating dof) {
+ outputHash = dof;
+ },
+ }, i.second.output);
 
  if (outputHash.method == FileIngestionMethod::Flat) {
  /* The output path should be a regular file without execute permission. */
@@ -3737,22 +3750,33 @@ void DerivationGoal::registerOutputs()
  /* Check the hash. In hash mode, move the path produced by
  the derivation to its content-addressed location. */
  Hash h2 = outputHash.method == FileIngestionMethod::Recursive
- ? hashPath(*outputHash.hash.type, actualPath).first
- : hashFile(*outputHash.hash.type, actualPath);
+ ? hashPath(outputHash.hashType, actualPath).first
+ : hashFile(outputHash.hashType, actualPath);
 
  auto dest = worker.store.makeFixedOutputPath(outputHash.method, h2, i.second.path(worker.store, drv->name).name());
 
- if (outputHash.hash != h2) {
+ // true if either floating CA, or incorrect fixed hash.
+ bool needsMove = true;
+
+ if (auto p = std::get_if<DerivationOutputFixed>(& i.second.output)) {
+ Hash & h = p->hash.hash;
+ if (h != h2) {
 
  /* Throw an error after registering the path as
  valid. */
  worker.hashMismatch = true;
  delayedException = std::make_exception_ptr(
  BuildError("hash mismatch in fixed-output derivation '%s':\n wanted: %s\n got: %s",
  worker.store.printStorePath(dest),
- outputHash.hash.to_string(SRI, true),
+ h.to_string(SRI, true),
  h2.to_string(SRI, true)));
+ } else {
+ // matched the fixed hash, so no move needed.
+ needsMove = false;
+ }
+ }
 
+ if (needsMove) {
  Path actualDest = worker.store.Store::toRealPath(dest);
 
  if (worker.store.isValidPath(dest))