From e9a1ddc594de6e6251bf06d732775dae2cabe4c8 Mon Sep 17 00:00:00 2001 From: JerryShih Date: Sun, 18 Nov 2018 03:15:17 +0800 Subject: FindThreads: Replace the pthread symbol checking in libc. With asan build, we will have the pthread_create() symbol in libc. However, libasan doesn't have full pthread implementation. We can't assume that we have the pthread implementation in libc using pthread_create() symbol. Replace the pthread_create() with pthread_kill() as a quick fix. --- Modules/FindThreads.cmake | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/Modules/FindThreads.cmake b/Modules/FindThreads.cmake index dfb683f..691b1b7 100644 --- a/Modules/FindThreads.cmake +++ b/Modules/FindThreads.cmake @@ -131,9 +131,17 @@ else() # set(CMAKE_HAVE_THREADS_LIBRARY) if(NOT THREADS_HAVE_PTHREAD_ARG) - # Check if pthread functions are in normal C library - CHECK_SYMBOL_EXISTS(pthread_create pthread.h CMAKE_HAVE_LIBC_CREATE) - if(CMAKE_HAVE_LIBC_CREATE) + # Check if pthread functions are in normal C library. + # If the pthread functions already exist in C library, we could just use + # them instead of linking to the additional pthread library. We could + # try to check any pthread symbol name, but here is an exception. If we + # use clang asan build, we will find the pthread_create() symbol in the + # libc(libasan). However, it doesn't have the full pthread implementation. + # So, we can't assume that we have the pthread implementation in libc + # using the pthread_create() checking here. Then, we turn to check the + # pthread_kill() symbol instead. + CHECK_SYMBOL_EXISTS(pthread_kill pthread.h CMAKE_HAVE_LIBC_PTHREAD_KILL) + if(CMAKE_HAVE_LIBC_PTHREAD_KILL) set(CMAKE_THREAD_LIBS_INIT "") set(CMAKE_HAVE_THREADS_LIBRARY 1) set(Threads_FOUND TRUE) @@ -159,7 +167,7 @@ else() endif() endif() -if(CMAKE_THREAD_LIBS_INIT OR CMAKE_HAVE_LIBC_CREATE) +if(CMAKE_THREAD_LIBS_INIT OR CMAKE_HAVE_LIBC_PTHREAD_KILL) set(CMAKE_USE_PTHREADS_INIT 1) set(Threads_FOUND TRUE) endif() -- cgit v0.12