[test][compiler-rt] Avoid LD_PRELOAD for "outer" dynamic linkers

[hubert.reinterpretcast]

Summary

This patch moves the setting of LD_PRELOAD "inwards" to avoid issues where the built library needs to be loaded with the dynamic linker that was configured with the build (and cannot, for example, be loaded by the dynamic linker associated with the env utility).

[hubert.reinterpretcast]

Ping.

[jsji]

issues where the built library needs to be loaded with the dynamic linker that was configured with the build (and cannot, for example, be loaded by the dynamic linker associated with the env utility).

No sure I understand the issues. %env_asan_opts will be substituted to env ASAN_OPTIONS=... in LIT run as well. If the libraray can NOT be loaded by the dynamic linker associated with env, then why it will work with env ASAN_OPTIONS=... .. LD_PRELOAD=... now?

[hubert.reinterpretcast]

In D79695#2049776, @jsji wrote:

No sure I understand the issues. %env_asan_opts will be substituted to env ASAN_OPTIONS=... in LIT run as well. If the libraray can NOT be loaded by the dynamic linker associated with env, then why it will work with env ASAN_OPTIONS=... .. LD_PRELOAD=... now?

This would be because the dynamic loader associated with env no longer has LD_PRELOAD set in its environment.

[nemanjai]

So if I interpret this correctly, the existing behaviour will end up with something like env LD_PRELOAD=<lib> env ASAN_OPTIONS=<opts> not ...
which will run the inner env with LD_PRELOAD set. This patch flattens this to have only one invocation of env and sets both environment variables for the actual command.

I think this makes sense as long as %env_asan_opts does not end up expanding to something different on some platform (which I don't imagine is the case judging by the name).

LGTM.

[jsji]

Thanks LGTM too.

compiler-rt/test/asan/TestCases/Linux/preinstalled_signal.cpp

 // RUN: %clangxx -std=c++11 %s -o %t
-// RUN: env LD_PRELOAD=%shared_libasan %env_asan_opts=handle_segv=1 not %run %t 2>&1 | FileCheck %s
-// RUN: env LD_PRELOAD=%shared_libasan %env_asan_opts=handle_segv=2 not %run %t 2>&1 | FileCheck %s
+// RUN: %env_asan_opts=handle_segv=1 LD_PRELOAD=%shared_libasan not %run %t 2>&1 | FileCheck %s
+// RUN: %env_asan_opts=handle_segv=2 LD_PRELOAD=%shared_libasan not %run %t 2>&1 | FileCheck %s
 
 // RUN: %clangxx -std=c++11 -DTEST_INSTALL_SIG_HANDLER %s -o %t
-// RUN: env LD_PRELOAD=%shared_libasan %env_asan_opts=handle_segv=0 not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-HANDLER
-// RUN: env LD_PRELOAD=%shared_libasan %env_asan_opts=handle_segv=1 not %run %t 2>&1 | FileCheck %s
-// RUN: env LD_PRELOAD=%shared_libasan %env_asan_opts=handle_segv=2 not %run %t 2>&1 | FileCheck %s
+// RUN: %env_asan_opts=handle_segv=0 LD_PRELOAD=%shared_libasan not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-HANDLER
+// RUN: %env_asan_opts=handle_segv=1 LD_PRELOAD=%shared_libasan not %run %t 2>&1 | FileCheck %s
+// RUN: %env_asan_opts=handle_segv=2 LD_PRELOAD=%shared_libasan not %run %t 2>&1 | FileCheck %s
 
 // RUN: %clangxx -std=c++11 -DTEST_INSTALL_SIG_ACTION %s -o %t
-// RUN: env LD_PRELOAD=%shared_libasan %env_asan_opts=handle_segv=0 not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-ACTION
-// RUN: env LD_PRELOAD=%shared_libasan %env_asan_opts=handle_segv=1 not %run %t 2>&1 | FileCheck %s
-// RUN: env LD_PRELOAD=%shared_libasan %env_asan_opts=handle_segv=2 not %run %t 2>&1 | FileCheck %s
+// RUN: %env_asan_opts=handle_segv=0 LD_PRELOAD=%shared_libasan not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-ACTION
+// RUN: %env_asan_opts=handle_segv=1 LD_PRELOAD=%shared_libasan not %run %t 2>&1 | FileCheck %s
+// RUN: %env_asan_opts=handle_segv=2 LD_PRELOAD=%shared_libasan not %run %t 2>&1 | FileCheck %s
 
 // REQUIRES: asan-dynamic-runtime
 
 // This way of setting LD_PRELOAD does not work with Android test runner.
 // REQUIRES: !android
 
 #include <assert.h>
 #include <signal.h>