Fix zstd build when static zstd libraries are not avilable

Author: uditagarwal97

buildbot/configure.py

@@ -64,7 +64,7 @@ def do_configure(args):
 
     sycl_enable_xpti_tracing = "ON"
     xpti_enable_werror = "OFF"
-    llvm_enable_zstd = "OFF"
+    llvm_enable_zstd = "ON"
 
     if sys.platform != "darwin":
         sycl_enabled_backends.append("level_zero")
@@ -134,8 +134,6 @@ def do_configure(args):
 
         # For clang-format, clang-tidy and code coverage
         llvm_enable_projects += ";clang-tools-extra;compiler-rt"
-        # Build with zstd enabled on CI.
-        llvm_enable_zstd = "ON"
         if sys.platform != "darwin":
             # libclc is required for CI validation
             libclc_enabled = True

llvm/cmake/config-ix.cmake

@@ -157,7 +157,14 @@ if(LLVM_ENABLE_ZSTD)
     find_package(zstd QUIET)
   endif()
 endif()
+
+# If LLVM_USE_STATIC_ZSTD is specified, make sure we enable zstd only if static
+# libraries are found.
+if(LLVM_USE_STATIC_ZSTD AND NOT TARGET zstd::libzstd_static)
+set(LLVM_ENABLE_ZSTD OFF)
+else()
 set(LLVM_ENABLE_ZSTD ${zstd_FOUND})
+endif()
 
 if(LLVM_ENABLE_LIBXML2)
   if(LLVM_ENABLE_LIBXML2 STREQUAL FORCE_ON)