Mac build failure when using case sensitive filesystem

I am getting build failures on my Mac Book Pro running Sierra 10.12.3 that is using a case sensitive file system.

My clone of the repo is at commit 080235a on the 4.15 branch

The build failure error messages are:

Showing Recent Issues
Running UnrealHeaderTool UE4Editor “/Users//Projects/EpicGames/UnrealEngine/Engine/Intermediate/Build/Mac/UE4Editor/Development/UE4Editor.uhtmanifest” -LogCmds=“loginit warning, logexit warning, logdatabase error” -Unattended -WarningsAsErrors
Reflection code generated for UE4Editor in 11.578471 seconds
ERROR: System.IO.FileNotFoundException: Could not find file “/Users//Projects/EpicGames/UnrealEngine/Engine/Plugins/Experimental/AlembicImporter/Intermediate/Build/Mac/UE4Editor/Inc/AlembicLibrary/AlembicTestCommandLet.generated.h”.
File name: ‘/Users//Projects/EpicGames/UnrealEngine/Engine/Plugins/Experimental/AlembicImporter/Intermediate/Build/Mac/UE4Editor/Inc/AlembicLibrary/AlembicTestCommandLet.generated.h’