<div dir="ltr"><div>Hello,<br></div><div><br></div><div>I want to add a field for collecting information about the number of GCs a</div>particular heap object survived.<br><br>I've done the following to implement this:<br>- Add a field "StgWord gc_id" to struct "StgHeader" and "StgThunkHeader"<br>- Update "SET_HDR" macro in "ClosureMacros.h" to update the "gc_id"<br>- Update the "closureTypeHeaderSize" function in "Heap/ClosureTypes.hs" to<br>  account for that 1 extra word.<br><br>Compilation leads to a segmentation fault. The stage 2 compiler is built. But<br>usage of it leads to a segmentation fault.<br><br>Build output:<br>```<br>chmod +x                                                     inplace/bin/ghc-stage2<br>"inplace/bin/ghc-stage2" -hisuf dyn_hi -osuf  dyn_o -hcsuf dyn_hc -fPIC -dynamic  -O0 -H64m -Wall      -hide-all-packages -package-env - -i -iutils/check-api-annotations/. -iutils/check-api-annotations/dist-install/build -Iutils/check-api-annotations/dist-install/build -iutils/check-api-annotations/dist-install/build/check-api-annotations/autogen -Iutils/check-api-annotations/dist-install/build/check-api-annotations/autogen     -optP-include -optPutils/check-api-annotations/dist-install/build/check-api-annotations/autogen/cabal_macros.h -package-id Cabal-3.2.1.0 -package-id base-4.14.3.0 -package-id containers-0.6.5.1 -package-id directory-1.3.6.0 -package-id ghc-8.10.7.20240224 -Wall -XHaskell2010  -no-user-package-db -rtsopts       -Wnoncanonical-monad-instances  -outputdir utils/check-api-annotations/dist-install/build   -c utils/check-api-annotations/./Main.hs -o utils/check-api-annotations/dist-install/build/Main.dyn_o<br>utils/check-api-annotations/<a href="http://ghc.mk:18">ghc.mk:18</a>: recipe for target 'utils/check-api-annotations/dist-install/build/Main.dyn_o' failed<br>make[1]: *** [utils/check-api-annotations/dist-install/build/Main.dyn_o] Segmentation fault (core dumped)<br>Makefile:123: recipe for target 'all' failed<br>make: *** [all] Error 2<br>```<br><br>Is there any other place I've missed follow-up modifications?<br><br><div>I appreciate any help  provided.</div><div><br></div>Best,<br>Adithya<br></div>