1714305 - readability-simplify-boolean-expr --fix generates invalid code

Status: NEW

(Developer Infrastructure :: Source Code Analysis, defect, P3)

Description

[Valentin Gosu [:valentin]]

Ran ./mach static-analysis check netwerk/ --fix

24:03.06  /home/icecold/mozilla-central/netwerk/ipc/SocketProcessChild.cpp
24:03.06 Warning: readability-simplify-boolean-expr in netwerk/ipc/SocketProcessChild.cpp: redundant boolean literal in conditional return statement
24:03.06 /home/icecold/mozilla-central/netwerk/ipc/SocketProcessChild.cpp:148:12: warning: redundant boolean literal in conditional return statement [readability-simplify-boolean-expr]
24:03.06     return false;
24:03.06 ~~~~~~~~~~~^~~~~~

Generated replaced these lines with the following:

  return  == 0;

Which is obviously wrong and doesn't build.
I assume it was going for return rv == 0;

Comment 1

[Valentin Gosu [:valentin]]

Second (similar) bug

28:03.07 Warning: readability-else-after-return in netwerk/protocol/http/AltSvcTransactionParent.cpp: do not use 'else' after 'return'
28:03.07 /home/icecold/mozilla-central/netwerk/protocol/http/AltSvcTransactionParent.cpp:21:3: warning: do not use 'else' after 'return' [readability-else-after-return]
28:03.07   NS_INTERFACE_MAP_ENTRY_CONCRETE(AltSvcTransactionParent)
28:03.07   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
28:03.07 /home/icecold/mozilla-central/obj-x86_64-pc-linux-gnu/dist/include/nsISupportsImpl.h:1297:3: note: expanded from macro 'NS_INTERFACE_MAP_ENTRY_CONCRETE'
28:03.07   NS_IMPL_QUERY_BODY_CONCRETE(_class)
28:03.07   ^
28:03.07 /home/icecold/mozilla-central/obj-x86_64-pc-linux-gnu/dist/include/nsISupportsImpl.h:1227:5: note: expanded from macro 'NS_IMPL_QUERY_BODY_CONCRETE'
28:03.07   } else
28:03.07     ^

turned NS_INTERFACE_MAP_ENTRY_CONCRETE(AltSvcTransactionParent) into

AltSvcTransactionParent)

Comment 2

[Andi [:andi]]

Here is a more general problem with how this checker treats macro definitions, instead of trying an autofix it should branch out by not giving a solution, since in this context we cannot guarantee that there is a solution.