1 files changed, 1 insertions, 93 deletions
diff --git a/doc/build-osx.md b/doc/build-osx.md
index bf655538c7..7b76117c8b 100644
--- a/doc/build-osx.md
+++ b/doc/build-osx.md
@@ -22,6 +22,7 @@ Then install [Homebrew](https://brew.sh).
 brew install automake berkeley-db4 libtool boost miniupnpc pkg-config python qt libevent qrencode
 ```
 
+If you run into issues, check [Homebrew's troubleshooting page](https://docs.brew.sh/Troubleshooting).
 See [dependencies.md](dependencies.md) for a complete overview.
 
 If you want to build the disk image with `make deploy` (.dmg / optional), you need RSVG:
@@ -113,96 +114,3 @@ tail -f $HOME/Library/Application\ Support/Bitcoin/debug.log
 * Tested on OS X 10.12 Sierra through macOS 10.15 Catalina on 64-bit Intel
 processors only.
 * Building with downloaded Qt binaries is not officially supported. See the notes in [#7714](https://github.com/bitcoin/bitcoin/issues/7714).
-
-## Deterministic macOS DMG Notes
-Working macOS DMGs are created in Linux by combining a recent `clang`, the Apple
-`binutils` (`ld`, `ar`, etc) and DMG authoring tools.
-
-Apple uses `clang` extensively for development and has upstreamed the necessary
-functionality so that a vanilla clang can take advantage. It supports the use of `-F`,
-`-target`, `-mmacosx-version-min`, and `--sysroot`, which are all necessary when
-building for macOS.
-
-Apple's version of `binutils` (called `cctools`) contains lots of functionality missing in the
-FSF's `binutils`. In addition to extra linker options for frameworks and sysroots, several
-other tools are needed as well such as `install_name_tool`, `lipo`, and `nmedit`. These
-do not build under Linux, so they have been patched to do so. The work here was used as
-a starting point: [mingwandroid/toolchain4](https://github.com/mingwandroid/toolchain4).
-
-In order to build a working toolchain, the following source packages are needed from
-Apple: `cctools`, `dyld`, and `ld64`.
-
-These tools inject timestamps by default, which produce non-deterministic binaries. The
-`ZERO_AR_DATE` environment variable is used to disable that.
-
-This version of `cctools` has been patched to use the current version of `clang`'s headers
-and its `libLTO.so` rather than those from `llvmgcc`, as it was originally done in `toolchain4`.
-
-To complicate things further, all builds must target an Apple SDK. These SDKs are free to
-download, but not redistributable. To obtain it, register for an Apple Developer Account,
-then download the [Xcode 7.3.1 dmg](https://developer.apple.com/devcenter/download.action?path=/Developer_Tools/Xcode_7.3.1/Xcode_7.3.1.dmg).
-
-This file is several gigabytes in size, but only a single directory inside is needed:
-```
-Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.11.sdk
-```
-
-Unfortunately, the usual Linux tools (7zip, hpmount, loopback mount) are incapable of
-opening this file. To create a tarball suitable for Gitian input, there are two options:
-
-Using macOS, you can mount the DMG, and then create it with:
-```shell
-hdiutil attach Xcode_7.3.1.dmg
-tar -C /Volumes/Xcode/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/ -czf MacOSX10.11.sdk.tar.gz MacOSX10.11.sdk
-```
-
-Alternatively, you can use 7zip and SleuthKit to extract the files one by one. The script
-[`extract-osx-sdk.sh`](./../contrib/macdeploy/extract-osx-sdk.sh) automates this. First
-ensure the DMG file is in the current directory, and then run the script. You may wish to
-delete the `intermediate 5.hfs` file and `MacOSX10.11.sdk` (the directory) when you've
-confirmed the extraction succeeded.
-
-```shell
-apt-get install p7zip-full sleuthkit
-contrib/macdeploy/extract-osx-sdk.sh
-rm -rf 5.hfs MacOSX10.11.sdk
-```
-
-The Gitian descriptors build 2 sets of files: Linux tools, then Apple binaries which are
-created using these tools. The build process has been designed to avoid including the
-SDK's files in Gitian's outputs. All interim tarballs are fully deterministic and may be freely
-redistributed.
-
-`genisoimage` is used to create the initial DMG. It is not deterministic as-is, so it has been
-patched. A system `genisoimage` will work fine, but it will not be deterministic because
-the file-order will change between invocations. The patch can be seen here:  [theuni/osx-cross-depends](https://raw.githubusercontent.com/theuni/osx-cross-depends/master/patches/cdrtools/genisoimage.diff).
-No effort was made to fix this cleanly, so it likely leaks memory badly. But it's only used for
-a single invocation, so that's no real concern.
-
-`genisoimage` cannot compress DMGs, so afterwards, the DMG tool from the
-`libdmg-hfsplus` project is used to compress it. There are several bugs in this tool and its
-maintainer has seemingly abandoned the project. It has been forked and is available
-(with fixes) here: [theuni/libdmg-hfsplus](https://github.com/theuni/libdmg-hfsplus).
-
-The DMG tool has the ability to create DMGs from scratch as well, but this functionality is
-broken. Only the compression feature is currently used. Ideally, the creation could be fixed
-and `genisoimage` would no longer be necessary.
-
-Background images and other features can be added to DMG files by inserting a
-`.DS_Store` before creation. This is generated by the script
-`contrib/macdeploy/custom_dsstore.py`.
-
-As of OS X 10.9 Mavericks, using an Apple-blessed key to sign binaries is a requirement in
-order to satisfy the new Gatekeeper requirements. Because this private key cannot be
-shared, we'll have to be a bit creative in order for the build process to remain somewhat
-deterministic. Here's how it works:
-
-- Builders use Gitian to create an unsigned release. This outputs an unsigned DMG which
-  users may choose to bless and run. It also outputs an unsigned app structure in the form
-  of a tarball, which also contains all of the tools that have been previously (deterministically)
-  built in order to create a final DMG.
-- The Apple keyholder uses this unsigned app to create a detached signature, using the
-  script that is also included there. Detached signatures are available from this [repository](https://github.com/bitcoin-core/bitcoin-detached-sigs).
-- Builders feed the unsigned app + detached signature back into Gitian. It uses the
-  pre-built tools to recombine the pieces into a deterministic DMG.
-