diff --git a/gcc/d/ChangeLog b/gcc/d/ChangeLog
index 55cf98f5bd1..6fa01f57897 100644
--- a/gcc/d/ChangeLog
+++ b/gcc/d/ChangeLog
@@ -1,3 +1,7 @@
+2019-01-12  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	* README.gcc: New file.
+
 2019-01-01  Jakub Jelinek  <jakub@redhat.com>
 
 	Update copyright years.
diff --git a/gcc/d/README.gcc b/gcc/d/README.gcc
new file mode 100644
index 00000000000..757545cc705
--- /dev/null
+++ b/gcc/d/README.gcc
@@ -0,0 +1,11 @@
+The files in the dmd subdirectory are part of the front-end for the
+Digital Mars D compiler, hosted at https://github.com/dlang/dmd/.
+
+They cover the lexical analysis, parsing, and semantic analysis of the
+D Programming Language defined in the documents at https://dlang.org/.
+
+To report a problem or look up known issues with the dmd front-end,
+please visit the issue tracker at https://issues.dlang.org/.
+
+All changes to dmd should go through the upstream repository first,
+then merged back to GCC.
diff --git a/libphobos/ChangeLog b/libphobos/ChangeLog
index 2f192dba8dd..04bfcafad15 100644
--- a/libphobos/ChangeLog
+++ b/libphobos/ChangeLog
@@ -1,3 +1,7 @@
+2019-01-12  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	* README.gcc: New file.
+
 2019-01-01  Jakub Jelinek  <jakub@redhat.com>
 
 	Update copyright years.
diff --git a/libphobos/README.gcc b/libphobos/README.gcc
new file mode 100644
index 00000000000..53593783995
--- /dev/null
+++ b/libphobos/README.gcc
@@ -0,0 +1,26 @@
+The files in this directory where noted are part of the DRuntime
+and Phobos library.
+
+DRuntime is the low-level runtime library backing the D programming
+language, hosted at https://github.com/dlang/druntime/.
+
+Phobos is the standard library for the D Programming Language, hosted
+at https://github.com/dlang/phobos/.
+
+The following sources and directories are part of DRuntime:
+  libdruntime/core/
+  libdruntime/gc/
+  libdruntime/gcstub/
+  libdruntime/object.d
+  libdruntime/rt/
+
+The following sources and directories are part of Phobos:
+  src/etc/
+  src/index.d
+  src/std/
+
+To report a bug or look up known issues with the runtime or standard
+library please visit the issue tracker at https://issues.dlang.org/.
+
+All changes to either of these libraries should go through the
+upstream repository first, then merged back to GCC.