[NetBSD-PR lib/42900] pthread_create(3) deadlock in pthread_atfork(3)'s handler

[Takehiko NOZAKI]

see:

• http://gnats.netbsd.org/cgi-bin/query-pr-single.pl?number=42900
• https://bugs.ruby-lang.org/issues/2603

[Takehiko NOZAKI]

BUGFIX: Issue #67 -- [NetBSD-PR lib/42900] pthread_create(3) deadlock in pthread_atfork(3)'s handler.

→ <<cset 6fbf40a50ad2>>

[Takehiko NOZAKI]

Revert "BUGFIX: Issue #67 -- [NetBSD-PR lib/42900] pthread_create(3) deadlock in pthread_atfork(3)'s handler."

This reverts commit 6fbf40a50ad2218252002df9d0c47a6cc0249bb2.

→ <<cset f7a64134653a>>

[Takehiko NOZAKI]

this change seems broke rump_server(librumpuser), so i backed out.

[Takehiko NOZAKI]

rump_server crashes following reason:

1. because of dlsym(RTDL_NEXT)'s bug(see Issue #76), LD_PRELOAD=libpthread.so doesn't override libc's fork() by __weak_alias.
2. namespace.h force to use _fork() in other function that internally uses fork(2) such as daemon(3). so overriding libpthread's fork() by __weak_alias was suceeded, but still those function calls libc's fork().

[Takehiko NOZAKI]

BUGFIX: Issue #67 -- [NetBSD-PR lib/42900] pthread_create(3) deadlock in pthread_atfork(3)'s handler.

→ <<cset c921aa097634>>