[Driver] Set CLANG_DEFAULT_PIE_ON_LINUX OFF

GCC in major distros (such as RedHat) stays on no-pie by default.
Also GCC trunk is not going to change this default
(see https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103398).
Keeping this OFF for compatibility reasons.

Author: Pavel V Chupin

clang/CMakeLists.txt

@@ -245,7 +245,9 @@ set(PPC_LINUX_DEFAULT_IEEELONGDOUBLE OFF CACHE BOOL
 set(CLANG_SPAWN_CC1 OFF CACHE BOOL
     "Whether clang should use a new process for the CC1 invocation")
 
-option(CLANG_DEFAULT_PIE_ON_LINUX "Default to -fPIE and -pie on linux-gnu" ON)
+# Turn this OFF downstream for compatibility reasons. GCC default is no-pie
+# and many distros, e.g. RedHat has no-pie by default for GCC.
+option(CLANG_DEFAULT_PIE_ON_LINUX "Default to -fPIE and -pie on linux-gnu" OFF)
 
 # Manually handle default so we can change the meaning of a cached default.
 set(CLANG_ENABLE_OPAQUE_POINTERS "DEFAULT" CACHE STRING

clang/test/Driver/clang-offload-wrapper-exe.cpp

@@ -25,7 +25,7 @@
 // --- Create the wrapper object
 // -host omitted - generate object for the host triple:
 // RUN: clang-offload-wrapper -kind=sycl -target=TARGET -format=native -batch %t.batch -o %t.wrapped.bc
-// RUN: llc --filetype=obj %t.wrapped.bc -o %t.wrapped.o --relocation-model=pic
+// RUN: llc --filetype=obj %t.wrapped.bc -o %t.wrapped.o
 // --- Compile & link the test with the wrapper
 // RUN: %clangxx %t.wrapped.o %s -o %t.batch.exe -v
 // --- Run and check ignoring white spaces