Modify Nmax to maxN Trac #10728

Added test and changed -Nmax to -maxN, -n was taken

Noticed strange -m behavoir and fixed -m from quietly
ignoring being passed invalid opts, e.g. "-msasd"

Reviewers: simonmar, hvr, austin, thomie, bgamari

Reviewed By: hvr, thomie, bgamari

Subscribers: bgamari, hvr, thomie, simonmar

Differential Revision: https://phabricator.haskell.org/D1677

GHC Trac Issues: #10728

3 files changed, 49 insertions, 5 deletions

diff --git a/testsuite/tests/rts/T10728.hs b/testsuite/tests/rts/T10728.hs
new file mode 100644
index 0000000000..056124d0ca
--- /dev/null
+++ b/testsuite/tests/rts/T10728.hs
@@ -0,0 +1,40 @@
+-- T10728 test case for ``-maxN<n>``
+
+module Main where
+
+import GHC.Conc (getNumProcessors, getNumCapabilities)
+import GHC.Environment
+import Data.Char
+
+main :: IO ()
+main = do
+  -- We're parsing args passed in to make sure things are proper between the
+  -- cli and the program.
+  n <- getN
+
+  c <- getNumCapabilities
+  p <- getNumProcessors
+
+  putStr $ check n c p
+
+-----
+
+check :: Int -> Int -> Int -> String
+check n c p
+  |  n /= 0 && c /= 0 && p /= 0 -- These should never be 0
+  -- Capabilities are equal to n, are they also within processor count?
+  && (n == c && c <= p)
+  -- Capabilities are equal to processor count, are they also within n?
+  || (c == p && c <= n)
+  = "maxN Successful"
+check _n _c _p = "maxN Error"
+
+-- Parsing ``-maxN<n>`` from Args to be sure of it.
+getN :: IO Int
+getN = getFullArgs >>= return . go
+  where
+    go :: [String] -> Int
+    go as = case reads (
+      dropWhile (not . isDigit) . (!! 1) $ as ) :: [(Int, String)] of
+        [x] -> fst x
+        _ -> 0
diff --git a/testsuite/tests/rts/T10728.stdout b/testsuite/tests/rts/T10728.stdout
new file mode 100644
index 0000000000..715329ea3c
--- /dev/null
+++ b/testsuite/tests/rts/T10728.stdout
@@ -0,0 +1 @@
+maxN Successful
diff --git a/testsuite/tests/rts/all.T b/testsuite/tests/rts/all.T
index 9892050b34..c88bd62267 100644
--- a/testsuite/tests/rts/all.T
+++ b/testsuite/tests/rts/all.T
@@ -1,9 +1,9 @@
 test('testblockalloc',
-     [c_src, only_ways(['normal','threaded1']), extra_run_opts('+RTS -I0')], 
+     [c_src, only_ways(['normal','threaded1']), extra_run_opts('+RTS -I0')],
      compile_and_run, [''])
 
 test('testmblockalloc',
-     [c_src, only_ways(['normal','threaded1']), extra_run_opts('+RTS -I0')], 
+     [c_src, only_ways(['normal','threaded1']), extra_run_opts('+RTS -I0')],
      compile_and_run, [''])
 # -I0 is important: the idle GC will run the memory leak detector,
 # which will crash because the mblocks we allocate are not in a state
@@ -53,7 +53,7 @@ test('divbyzero',
       when(opsys('mingw32'), omit_ways(prof_ways))],
      compile_and_run, [''])
 
-test('outofmem', when(opsys('darwin'), skip), 
+test('outofmem', when(opsys('darwin'), skip),
                  run_command, ['$MAKE -s --no-print-directory outofmem'])
 test('outofmem2', extra_run_opts('+RTS -M5m -RTS'),
                   run_command, ['$MAKE -s --no-print-directory outofmem2'])
@@ -111,8 +111,8 @@ test('T2615',
 
 # omit dyn and profiling ways, because we don't build dyn_l or p_l
 # variants of the RTS by default
-test('traceEvent', [ omit_ways(['dyn'] + prof_ways), 
-                     extra_run_opts('+RTS -ls -RTS') ], 
+test('traceEvent', [ omit_ways(['dyn'] + prof_ways),
+                     extra_run_opts('+RTS -ls -RTS') ],
                    compile_and_run, ['-eventlog'])
 
 test('T4059',
@@ -333,3 +333,6 @@ test('T10590', [ignore_output, when(opsys('mingw32'),skip)], compile_and_run, ['
 # 20000 was easily enough to trigger the bug with 7.10
 test('T10904', [ omit_ways(['ghci']), extra_run_opts('20000') ],
                compile_and_run, ['T10904lib.c'])
+
+test('T10728', [extra_run_opts('+RTS -maxN3 -RTS'), req_smp],
+           compile_and_run, ['-threaded'])