[gentoo-dev] [PATCH] cmake-utils.eclass: Make the new ASM-ATT rules actually work

[James Le Cuirot <chewi@gentoo.org>]

The previous attempt actually broke ASM in media-libs/vulkan-loader
entirely so that it fell back to C code. After much experimentation
and combing through strace output, I found that -x assembler is needed
to handle non-standard file extentions and linking is done as a
separate step. CMAKE_ASM-ATT_LINK_FLAGS therefore needs to be defined
with -nostdlib to avoid errors about undefined main symbols.

Closes: https://bugs.gentoo.org/625844
---
One user has confirmed that this patch works for vulkan-loader and I'd
like a dev or two to also confirm this before I merge.

 eclass/cmake-utils.eclass | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/eclass/cmake-utils.eclass b/eclass/cmake-utils.eclass
index f8853be502a1..f6952ec09efd 100644
--- a/eclass/cmake-utils.eclass
+++ b/eclass/cmake-utils.eclass
@@ -520,7 +520,8 @@ cmake-utils_src_configure() {
 	fi
 	cat > "${build_rules}" <<- _EOF_ || die
 		SET (CMAKE_ASM_COMPILE_OBJECT "<CMAKE_ASM_COMPILER> <DEFINES> ${includes} ${CPPFLAGS} <FLAGS> -o <OBJECT> -c <SOURCE>" CACHE STRING "ASM compile command" FORCE)
-		SET (CMAKE_ASM-ATT_COMPILE_OBJECT "<CMAKE_ASM_COMPILER> <DEFINES> ${includes} ${CPPFLAGS} <FLAGS> -o <OBJECT> -c <SOURCE>" CACHE STRING "ASM compile command" FORCE)
+		SET (CMAKE_ASM-ATT_COMPILE_OBJECT "<CMAKE_ASM-ATT_COMPILER> <DEFINES> ${includes} ${CPPFLAGS} <FLAGS> -o <OBJECT> -c -x assembler <SOURCE>" CACHE STRING "ASM-ATT compile command" FORCE)
+		SET (CMAKE_ASM-ATT_LINK_FLAGS "-nostdlib" CACHE STRING "ASM-ATT link flags" FORCE)
 		SET (CMAKE_C_COMPILE_OBJECT "<CMAKE_C_COMPILER> <DEFINES> ${includes} ${CPPFLAGS} <FLAGS> -o <OBJECT> -c <SOURCE>" CACHE STRING "C compile command" FORCE)
 		SET (CMAKE_CXX_COMPILE_OBJECT "<CMAKE_CXX_COMPILER> <DEFINES> ${includes} ${CPPFLAGS} <FLAGS> -o <OBJECT> -c <SOURCE>" CACHE STRING "C++ compile command" FORCE)
 		SET (CMAKE_Fortran_COMPILE_OBJECT "<CMAKE_Fortran_COMPILER> <DEFINES> ${includes} ${FCFLAGS} <FLAGS> -o <OBJECT> -c <SOURCE>" CACHE STRING "Fortran compile command" FORCE)
-- 
2.16.1