From 8e38985db7cb2c66f7fe74919e03e3f3ae0d0c41 Mon Sep 17 00:00:00 2001
From: Brad King <brad.king@kitware.com>
Date: Wed, 7 Apr 2021 09:50:10 -0400
Subject: Makefiles: Fix dependency extraction with CUDA < 10.2 and host
 compiler

Since commit 2c71d051fa (Makefiles Generators: use compiler for
dependencies generation, 2020-10-18, v3.20.0-rc1~392^2) we invoke `nvcc`
for CUDA < 10.2 a second time in order to generate a depfile.  When
`CMAKE_CUDA_HOST_COMPILER` is set, the second invocation is missing its
`-ccbin=` option, even after refactoring in commit 8981e3e7cc
(NVIDIA-CUDA: rely on new capabilities for deps generation, 2020-12-02,
v3.20.0-rc1~362^2).

Ideally we should move the `-ccbin=` flag into `Compiler/NVIDIA-CUDA`,
but that will add `CMAKE_CUDA_HOST_COMPILER` support on Windows in
command-line generators but not the Visual Studio generators.
For now, add the flag to the depfile command specifically.

Fixes: #22037
---
 Modules/CMakeCUDAInformation.cmake |  3 +++
 Modules/Compiler/NVIDIA-CUDA.cmake | 10 +++++++++-
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/Modules/CMakeCUDAInformation.cmake b/Modules/CMakeCUDAInformation.cmake
index cb03ef4..5fd54c1 100644
--- a/Modules/CMakeCUDAInformation.cmake
+++ b/Modules/CMakeCUDAInformation.cmake
@@ -111,6 +111,9 @@ include(CMakeCommonLanguageInclude)
 # CMAKE_CUDA_LINK_EXECUTABLE
 
 if(CMAKE_CUDA_HOST_COMPILER AND CMAKE_CUDA_COMPILER_ID STREQUAL "NVIDIA")
+  # FIXME: This is too late for the Platform/Windows-NVIDIA-CUDA module to
+  # see it, so we do not support CMAKE_CUDA_HOST_COMPILER on Windows.
+  # Move this to Compiler/NVIDIA-CUDA and update the VS generator too.
   string(APPEND _CMAKE_CUDA_EXTRA_FLAGS " -ccbin=<CMAKE_CUDA_HOST_COMPILER>")
 endif()
 
diff --git a/Modules/Compiler/NVIDIA-CUDA.cmake b/Modules/Compiler/NVIDIA-CUDA.cmake
index eb80675..a0f7c05 100644
--- a/Modules/Compiler/NVIDIA-CUDA.cmake
+++ b/Modules/Compiler/NVIDIA-CUDA.cmake
@@ -30,7 +30,15 @@ if (CMAKE_CUDA_COMPILER_VERSION VERSION_GREATER_EQUAL 10.2.89)
   # to get header dependency information
   set(CMAKE_DEPFILE_FLAGS_CUDA "-MD -MT <DEP_TARGET> -MF <DEP_FILE>")
 else()
-  set(CMAKE_CUDA_DEPENDS_EXTRA_COMMANDS "<CMAKE_CUDA_COMPILER> ${_CMAKE_CUDA_EXTRA_FLAGS} <DEFINES> <INCLUDES> <FLAGS> ${_CMAKE_COMPILE_AS_CUDA_FLAG} -M <SOURCE> -MT <OBJECT> -o <DEP_FILE>")
+  if(CMAKE_CUDA_HOST_COMPILER AND NOT CMAKE_SYSTEM_NAME STREQUAL "Windows")
+    # FIXME: Move the main -ccbin= flag from CMakeCUDAInformation to
+    # a block above, remove this copy, and update the VS generator too.
+    set(_CMAKE_CUDA_EXTRA_FLAGS_LOCAL " -ccbin=<CMAKE_CUDA_HOST_COMPILER>")
+  else()
+    set(_CMAKE_CUDA_EXTRA_FLAGS_LOCAL "")
+  endif()
+  set(CMAKE_CUDA_DEPENDS_EXTRA_COMMANDS "<CMAKE_CUDA_COMPILER> ${_CMAKE_CUDA_EXTRA_FLAGS}${_CMAKE_CUDA_EXTRA_FLAGS_LOCAL} <DEFINES> <INCLUDES> <FLAGS> ${_CMAKE_COMPILE_AS_CUDA_FLAG} -M <SOURCE> -MT <OBJECT> -o <DEP_FILE>")
+  unset(_CMAKE_CUDA_EXTRA_FLAGS_LOCAL)
 endif()
 set(CMAKE_CUDA_DEPFILE_FORMAT gcc)
 if((NOT DEFINED CMAKE_DEPENDS_USE_COMPILER OR CMAKE_DEPENDS_USE_COMPILER)
-- 
cgit v0.12