CUDA official GCC conflicts (#25054)

* update CUDA 11 / GCC compatibility range

* additional unofficial conflict

* minor changes to comments

1 files changed, 21 insertions, 6 deletions

diff --git a/lib/spack/spack/build_systems/cuda.py b/lib/spack/spack/build_systems/cuda.py
index 79d63fab10..e7ae26f3c9 100644
--- a/lib/spack/spack/build_systems/cuda.py
+++ b/lib/spack/spack/build_systems/cuda.py
@@ -86,6 +86,27 @@ class CudaPackage(PackageBase):
     # apply to platform=darwin. We currently do not provide conflicts for
     # platform=darwin with %apple-clang.
 
+    # GCC
+    # According to
+    # https://github.com/spack/spack/pull/25054#issuecomment-886531664
+    # these conflicts are valid independently from the architecture
+
+    # minimum supported versions
+    conflicts('%gcc@:4', when='+cuda ^cuda@11.0:')
+    conflicts('%gcc@:5', when='+cuda ^cuda@11.4:')
+
+    # maximum supported version
+    # NOTE:
+    # in order to not constrain future cuda version to old gcc versions,
+    # it has been decided to use an upper bound for the latest version.
+    # This implies that the last one in the list has to be updated at
+    # each release of a new cuda minor version.
+    conflicts('%gcc@10:', when='+cuda ^cuda@:11.0')
+    conflicts('%gcc@11:', when='+cuda ^cuda@:11.4')
+
+    # https://gist.github.com/ax3l/9489132#gistcomment-3860114
+    conflicts('%gcc@10', when='+cuda ^cuda@:11.4.0')
+
     # Linux x86_64 compiler conflicts from here:
     # https://gist.github.com/ax3l/9489132
     with when('~allow-unsupported-compilers'):
@@ -94,9 +115,6 @@ class CudaPackage(PackageBase):
         conflicts('%gcc@7:', when='+cuda ^cuda@:9.1 target=x86_64:')
         conflicts('%gcc@8:', when='+cuda ^cuda@:10.0.130 target=x86_64:')
         conflicts('%gcc@9:', when='+cuda ^cuda@:10.2.89 target=x86_64:')
-        conflicts('%gcc@:4', when='+cuda ^cuda@11.0.2: target=x86_64:')
-        conflicts('%gcc@10:', when='+cuda ^cuda@:11.0.3 target=x86_64:')
-        conflicts('%gcc@11:', when='+cuda ^cuda@:11.1.0 target=x86_64:')
         conflicts('%pgi@:14.8', when='+cuda ^cuda@:7.0.27 target=x86_64:')
         conflicts('%pgi@:15.3,15.5:', when='+cuda ^cuda@7.5 target=x86_64:')
         conflicts('%pgi@:16.2,16.0:16.3', when='+cuda ^cuda@8 target=x86_64:')
@@ -130,9 +148,6 @@ class CudaPackage(PackageBase):
         conflicts('%gcc@8:', when='+cuda ^cuda@:10.0.130 target=ppc64le:')
         conflicts('%gcc@9:', when='+cuda ^cuda@:10.1.243 target=ppc64le:')
         # officially, CUDA 11.0.2 only supports the system GCC 8.3 on ppc64le
-        conflicts('%gcc@:4', when='+cuda ^cuda@11.0.2: target=ppc64le:')
-        conflicts('%gcc@10:', when='+cuda ^cuda@:11.0.2 target=ppc64le:')
-        conflicts('%gcc@11:', when='+cuda ^cuda@:11.1.0 target=ppc64le:')
         conflicts('%pgi', when='+cuda ^cuda@:8 target=ppc64le:')
         conflicts('%pgi@:16', when='+cuda ^cuda@:9.1.185 target=ppc64le:')
         conflicts('%pgi@:17', when='+cuda ^cuda@:10 target=ppc64le:')