cuda: add dev variant and ABI variant for ncurses (#22536)

* ncurses: add variant +abi5 for version 5 ABI
* cuda: add variant dev, which makes cuda-gdb useable

- cuda-gdb needs libncurses.so.5, which most distros doesn't have
 see also https://docs.nvidia.com/cuda/cuda-gdb/index.html#common-issues-oss

var/spack/repos/builtin/packages/cuda/package.py

@@ -103,7 +103,12 @@ class Cuda(Package):
     # Mojave support -- only macOS High Sierra 10.13 is supported.
     conflicts('arch=darwin-mojave-x86_64')
 
+    variant('dev', default=False, description='Enable development dependencies, i.e to use cuda-gdb')
+
     depends_on('libxml2', when='@10.1.243:')
+    # cuda-gdb needs libncurses.so.5
+    # see https://docs.nvidia.com/cuda/cuda-gdb/index.html#common-issues-oss
+    depends_on('ncurses abi=5', type='run', when='+dev')
 
     provides('opencl@:1.2', when='@7:')
     provides('opencl@:1.1', when='@:6')

var/spack/repos/builtin/packages/ncurses/package.py

@@ -31,6 +31,10 @@ class Ncurses(AutotoolsPackage, GNUMirrorPackage):
     variant('termlib', default=True,
             description='Enables termlib features. This is an extra '
                         'lib and optional internal dependency.')
+    # Build ncurses with ABI compaitibility.
+    variant('abi', default='none', description='choose abi compatibility', values=('none', '5', '6'), multi=False)
+
+    conflicts('abi=6', when='@:5.9', msg='6 is not compatible with this release')
 
     depends_on('pkgconfig', type='build')
 
@@ -108,6 +112,10 @@ def configure(self, spec, prefix):
                          '--enable-tcap-names',
                          '--with-versioned-syms'))
 
+        abi = self.spec.variants['abi'].value
+        if abi != 'none':
+            opts.append('--with-abi-version=' + abi)
+
         prefix = '--prefix={0}'.format(prefix)
 
         configure = Executable('../configure')