Aksal/nuttx
3
1
Fork 1
mirror of https://github.com/apache/nuttx.git synced 2026-08-01 20:28:58 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 2

arch/x86: default CROSSDEV on a macOS host

Browse source 
arch/x86 set CROSSDEV only under Cygwin, so everywhere else the build used
the bare tool names and got the host compiler.  On Linux that is a native
gcc which can produce i486 ELF objects, which is what the board README
assumes.  On macOS it is Apple clang, and on Apple Silicon that cannot
target i386 in any form -- so there is no configuration in which the default
works and a cross toolchain is not optional.

Default it to i686-elf-, which Homebrew packages and which accepts the
-march=i486 -mtune=i486 already in ARCHCPUFLAGS.  arch/x86_64 has had
exactly this stanza for its own toolchain all along; this is the same shape.

The Cygwin assignment becomes ?= to match, so that a CROSSDEV passed in from
the environment or the command line is honoured rather than overridden.

Note for anyone tempted by the toolchain they already have: a 64-bit x86
compiler with -m32 is not a substitute unless it was built with multilib.
Homebrew's x86_64-elf-gcc compiles 32-bit objects perfectly happily and has
no 32-bit libgcc to link them against, so the entire build succeeds and only
the final link fails, on __udivdi3, __divdi3, __moddi3 and __udivmoddi4.
`x86_64-elf-gcc -print-multi-lib' prints just `.;', which is the toolchain
saying so up front.

Signed-off-by: Marco Casaroli <marco.casaroli@gmail.com>

Assisted-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
This commit is contained in:
Marco Casaroli 2026-07-27 05:05:44 +02:00 • committed by Alin Jerpelea
parent bc669f9b13
commit d5e6cd3aa5
1 changed files with 8 additions and 3 deletions
Download patch file Download diff file Expand all files Collapse all files

11
arch/x86/src/common/Toolchain.defs
View file

@ -44,11 +44,16 @@ ARCHCPUFLAGS += -m32
LDFLAGS += -m elf_i386
endif
# We have to use a cross-development toolchain under Cygwin because the native
# Cygwin toolchains don't generate ELF binaries.
# A cross-development toolchain is required under Cygwin, whose native
# toolchains don't generate ELF binaries, and on macOS, which has no i386 host
# compiler at all -- Apple clang cannot target i386 on Apple Silicon.
# arch/x86_64 defaults CROSSDEV the same way. Note that a 64-bit toolchain
# with -m32 is not a substitute unless it was built with multilib.
ifeq ($(CONFIG_WINDOWS_CYGWIN),y)
CROSSDEV = i486-nuttx-elf-
CROSSDEV ?= i486-nuttx-elf-
else ifeq ($(CONFIG_HOST_MACOS),y)
CROSSDEV ?= i686-elf-
endif
CC = $(CROSSDEV)gcc