#7850 exposes a stack allocation issue present since at least 8.8 to 9.2.4
Summary
A variant of #7850 (closed) seems to have returned, at least on GHC 9.2.4, macos 12.5
Steps to reproduce
ghc -O -rtsopts T7850.hs ; ./T7850 +RTS -s
Loaded package environment from /Users/gcolpitts/.ghc/x86_64-darwin-9.2.4/environments/default
65533
23,668,967,664 bytes allocated in the heap
99,144 bytes copied during GC
60,128 bytes maximum residency (2 sample(s))
29,400 bytes maximum slop
11 MiB total memory in use (0 MB lost due to fragmentation)
Tot time (elapsed) Avg pause Max pause
Gen 0 5642 colls, 0 par 0.205s 0.220s 0.0000s 0.0006s
Gen 1 2 colls, 0 par 0.000s 0.001s 0.0003s 0.0004s
INIT time 0.000s ( 0.004s elapsed)
MUT time 8.946s ( 8.961s elapsed)
GC time 0.206s ( 0.221s elapsed)
EXIT time 0.000s ( 0.000s elapsed)
Total time 9.152s ( 9.186s elapsed)
%GC time 0.0% (0.0% elapsed)
Alloc rate 2,645,732,942 bytes per MUT second
Productivity 97.8% of total user, 97.5% of total elapsed
bash-3.2$ ./T7850 +RTS -s -kc1m
65533
17,877,232 bytes allocated in the heap
10,352 bytes copied during GC
1,075,936 bytes maximum residency (2 sample(s))
1,053,984 bytes maximum slop
15 MiB total memory in use (0 MB lost due to fragmentation)
Tot time (elapsed) Avg pause Max pause
Gen 0 3 colls, 0 par 0.000s 0.000s 0.0001s 0.0002s
Gen 1 2 colls, 0 par 0.000s 0.001s 0.0006s 0.0006s
INIT time 0.000s ( 0.003s elapsed)
MUT time 3.271s ( 3.276s elapsed)
GC time 0.001s ( 0.002s elapsed)
EXIT time 0.000s ( 0.012s elapsed)
Total time 3.271s ( 3.293s elapsed)
%GC time 0.0% (0.0% elapsed)
Alloc rate 5,466,075 bytes per MUT second
Productivity 100.0% of total user, 99.5% of total elapsed
Expected behavior
Should get good performance and heap allocation without having to specify "-kc1m"