| ! In release 2.34, glibc removed libpthread as a separate library. All the |
| ! pthread_* functions were subsumed into libc, so linking that is sufficient. |
| ! However, when linking against older glibc builds, the explicit link of |
| ! -pthread will be required. More details are here: |
| ! |
| ! https://developers.redhat.com/articles/2021/12/17/why-glibc-234-removed-libpthread#the_developer_view |
| ! |
| ! This makes it difficult to write a test that requires the -pthread flag in |
| ! order to pass. Checking for the presence of -lpthread in the linker flags is |
| ! not reliable since the linker could just skip the flag altogether if it is |
| ! linking against a new libc implementation. |
| |
| ! RUN: %flang -### -pthread /dev/null -o /dev/null 2>&1 | FileCheck %s |
| ! RUN: %flang -### -Xflang -pthread /dev/null -o /dev/null 2>&1 | FileCheck %s |
| |
| ! How the -pthread flag is handled is very platform-specific. A lot of that |
| ! functionality is tested by clang, and the flag itself is handled by clang's |
| ! driver that flang also uses. Instead of duplicating all that testing here, |
| ! just check that the presence of the flag does not raise an error. If we need |
| ! more customized handling of -pthread, the tests for that can be added here. |
| ! |
| ! CHECK-NOT: error: |
