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conan install libffi/3.4.2@ --build=libffi --profile=C:\J\w\BuildSingleReference@15/20732/df36a032-8137-488b-a93f-064d667f3fcc/profile.txt
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Configuration:
[settings]
arch=x86_64
arch_build=x86_64
build_type=Release
compiler=Visual Studio
compiler.runtime=MT
compiler.version=15
os=Windows
os_build=Windows
[options]
libffi:shared=False
[build_requires]
[env]

libffi/3.4.2: Forced build from source
Traceback (most recent call last):
  File "c:\python36\lib\site-packages\conans\client\command.py", line 2164, in run
    method(args[0][1:])
  File "c:\python36\lib\site-packages\conans\client\command.py", line 536, in install
    lockfile_node_id=args.lockfile_node_id)
  File "c:\python36\lib\site-packages\conans\client\conan_api.py", line 93, in wrapper
    return f(api, *args, **kwargs)
  File "c:\python36\lib\site-packages\conans\client\conan_api.py", line 560, in install_reference
    lockfile_node_id=lockfile_node_id)
  File "c:\python36\lib\site-packages\conans\client\manager.py", line 59, in deps_install
    lockfile_node_id=lockfile_node_id)
  File "c:\python36\lib\site-packages\conans\client\graph\graph_manager.py", line 120, in load_graph
    apply_build_requires=apply_build_requires)
  File "c:\python36\lib\site-packages\conans\client\graph\graph_manager.py", line 255, in _resolve_graph
    graph_lock=graph_lock)
  File "c:\python36\lib\site-packages\conans\client\graph\graph_manager.py", line 365, in _load_graph
    apply_build_requires=apply_build_requires)
  File "c:\python36\lib\site-packages\conans\client\graph\graph_manager.py", line 343, in _recurse_build_requires
    _recurse_build_requires(br_all, profile_build_requires)
  File "c:\python36\lib\site-packages\conans\client\graph\graph_manager.py", line 327, in _recurse_build_requires
    nodes_subset=nodessub, root=node)
  File "c:\python36\lib\site-packages\conans\client\graph\graph_manager.py", line 286, in _recurse_build_requires
    self._binary_analyzer.evaluate_graph(graph, build_mode, update, remotes, nodes_subset, root)
  File "c:\python36\lib\site-packages\conans\client\graph\graph_binaries.py", line 389, in evaluate_graph
    self._evaluate_node(node, build_mode, update, remotes)
  File "c:\python36\lib\site-packages\conans\client\graph\graph_binaries.py", line 176, in _evaluate_node
    self._process_node(node, pref, build_mode, update, remotes)
  File "c:\python36\lib\site-packages\conans\client\graph\graph_binaries.py", line 242, in _process_node
    self._evaluate_cache_pkg(node, package_layout, pref, metadata, remote, remotes, update)
  File "c:\python36\lib\site-packages\conans\client\graph\graph_binaries.py", line 95, in _evaluate_cache_pkg
    assert node.prev, "PREV for %s is None: %s" % (str(pref), metadata.dumps())
AssertionError: PREV for gnu-config/cci.20201022:5ab84d6acfe1f23c4fae0ab88f26e3a396351ac9 is None: {"recipe": {"revision": "c9b5dccbc620ae581bb1c60547ced620", "remote": "conan-center", "properties": {}, "checksums": {"conan_export.tgz": {"md5": "01ec85a77c93003990b0a7123f5886f1", "sha1": "6f71b0b82e093b7fab90e70fc19ef3eafb7ba1aa"}, "conanmanifest.txt": {"md5": "212e2e8cebbe3886f094e2834d40cf14", "sha1": "0bb80bef838223fac4864c42dc9b728270da1c61"}, "conanfile.py": {"md5": "add4439326e7c09165b9242748bb4175", "sha1": "c246ba1c15aa93325ec57e29bdf46492611f4f18"}}}, "packages": {"5ab84d6acfe1f23c4fae0ab88f26e3a396351ac9": {"revision": null, "recipe_revision": null, "remote": null, "properties": {}, "checksums": {}}}}

ERROR: PREV for gnu-config/cci.20201022:5ab84d6acfe1f23c4fae0ab88f26e3a396351ac9 is None: {"recipe": {"revision": "c9b5dccbc620ae581bb1c60547ced620", "remote": "conan-center", "properties": {}, "checksums": {"conan_export.tgz": {"md5": "01ec85a77c93003990b0a7123f5886f1", "sha1": "6f71b0b82e093b7fab90e70fc19ef3eafb7ba1aa"}, "conanmanifest.txt": {"md5": "212e2e8cebbe3886f094e2834d40cf14", "sha1": "0bb80bef838223fac4864c42dc9b728270da1c61"}, "conanfile.py": {"md5": "add4439326e7c09165b9242748bb4175", "sha1": "c246ba1c15aa93325ec57e29bdf46492611f4f18"}}}, "packages": {"5ab84d6acfe1f23c4fae0ab88f26e3a396351ac9": {"revision": null, "recipe_revision": null, "remote": null, "properties": {}, "checksums": {}}}}