cmake: toolchain/xt-clang: force assembler ID to GNU

xt-clang uses GNU Assembler (xt-as) based on binutils. However,
CMake doesn't recognize it when invoking through xt-clang. This
results in CMake going through all possible combinations of
command line arguments while invoking xt-clang to determine
assembler vendor. This multiple invocation of xt-clang
unnecessarily lengthens the CMake phase of build, especially
when xt-clang needs to obtain license information from remote
licensing servers. So here forces the assembler ID to be GNU to
speed things up a bit.

Signed-off-by: Daniel Leung <[email protected]>

Author: dcpleung

cmake/toolchain/xt-clang/generic.cmake

@@ -7,4 +7,14 @@ set(CC clang)
 set(C++ clang++)
 set(LINKER xt-ld)
 
+# xt-clang uses GNU Assembler (xt-as) based on binutils.
+# However, CMake doesn't recognize it when invoking through xt-clang.
+# This results in CMake going through all possible combinations of
+# command line arguments while invoking xt-clang to determine
+# assembler vendor. This multiple invocation of xt-clang unnecessarily
+# lengthens the CMake phase of build, especially when xt-clang needs to
+# obtain license information from remote licensing servers. So here
+# forces the assembler ID to be GNU to speed things up a bit.
+set(CMAKE_ASM_COMPILER_ID "GNU")
+
 message(STATUS "Found toolchain: xt-clang (${XTENSA_TOOLCHAIN_PATH})")