cmake: linker: make passing -no-pie configurable

This adds a new linker property specifically for passing "-no-pie" to linker. Older binutils' LD (<= 2.36) do not support this flag and will behave erratically if set. It would parse "-no-pie" separately as "-n" and "-o-pie", which would result in the output file being "-pie" instead of "zephyr*.elf". Moreover, LLVM lld does not support -no-pie but --no-pie (note the extra hyphen). By having no-pie as a linker property, we can pass correct no-pie flag to these linkers (or none at all). Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Willmish · Mar 29, 2023 · 81c3b31 · 81c3b31
1 parent 04fd862
commit 81c3b31
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Showing 6 changed files with 17 additions and 2 deletions.
diff --git a/CMakeLists.txt b/CMakeLists.txt
@@ -378,6 +378,7 @@ zephyr_compile_options($<$<COMPILE_LANGUAGE:CXX>:$<TARGET_PROPERTY:compiler-cpp,
 
 # @Intent: Do not make position independent code / executable
 zephyr_compile_options($<$<COMPILE_LANGUAGE:C>:$<TARGET_PROPERTY:compiler,no_position_independent>>)
+zephyr_link_libraries($<TARGET_PROPERTY:linker,no_position_independent>)
 
 # Allow the user to inject options when calling cmake, e.g.
 # 'cmake -DEXTRA_CFLAGS="-Werror -Wno-deprecated-declarations" ..'

diff --git a/cmake/linker/ld/linker_flags.cmake b/cmake/linker/ld/linker_flags.cmake
@@ -1,5 +1,15 @@
 check_set_linker_property(TARGET linker PROPERTY memusage "${LINKERFLAGPREFIX},--print-memory-usage")
 
+# -no-pie is not supported until binutils 2.37.
+# If -no-pie is passed to old binutils <= 2.36, it is parsed
+# as separate arguments -n and -o, which results in output file
+# called "-pie".
+if("${GNULD_VERSION_STRING}" VERSION_GREATER_EQUAL 2.37)
+  set_property(TARGET linker PROPERTY no_position_independent "${LINKERFLAGPREFIX},-no-pie")
+else()
+  set_property(TARGET linker PROPERTY no_position_independent)
+endif()
+
 # Some linker flags might not be purely ld specific, but a combination of
 # linker and compiler, such as:
 # --coverage for clang

diff --git a/cmake/linker/ld/target_base.cmake b/cmake/linker/ld/target_base.cmake
@@ -11,7 +11,6 @@ macro(toolchain_ld_base)
   # TOOLCHAIN_LD_FLAGS comes from compiler/gcc/target.cmake
   # LINKERFLAGPREFIX comes from linker/ld/target.cmake
   zephyr_ld_options(
-    -no-pie
     ${TOOLCHAIN_LD_FLAGS}
   )
 

diff --git a/cmake/linker/linker_flags_template.cmake b/cmake/linker/linker_flags_template.cmake
@@ -12,3 +12,7 @@ check_set_linker_property(TARGET linker PROPERTY memusage)
 
 # Extra warnings options for twister run
 set_property(TARGET linker PROPERTY warnings_as_errors)
+
+# Linker flag for disabling position independent binaries,
+# such as, "-no-pie" for LD, and "--no-pie" for LLD.
+set_property(TARGET linker PROPERTY no_position_independent)
diff --git a/cmake/linker/lld/linker_flags.cmake b/cmake/linker/lld/linker_flags.cmake
@@ -3,3 +3,5 @@
 
 # Since lld is a drop in replacement for ld, we can just use ld's flags
 include(${ZEPHYR_BASE}/cmake/linker/ld/${COMPILER}/linker_flags.cmake OPTIONAL)
+
+set_property(TARGET linker PROPERTY no_position_independent "${LINKERFLAGPREFIX},--no-pie")
diff --git a/cmake/linker/lld/target_base.cmake b/cmake/linker/lld/target_base.cmake
@@ -11,7 +11,6 @@ macro(toolchain_ld_base)
   # TOOLCHAIN_LD_FLAGS comes from compiler/clang/target.cmake
   # LINKERFLAGPREFIX comes from linker/lld/target.cmake
   zephyr_ld_options(
-    -no-pie
     ${TOOLCHAIN_LD_FLAGS}
   )
Original file line number	Diff line number	Diff line change
Expand Up		@@ -3,3 +3,5 @@

		# Since lld is a drop in replacement for ld, we can just use ld's flags
		include(${ZEPHYR_BASE}/cmake/linker/ld/${COMPILER}/linker_flags.cmake OPTIONAL)

		set_property(TARGET linker PROPERTY no_position_independent "${LINKERFLAGPREFIX},--no-pie")