cmake: don't set ARCH from CMAKE_SYSTEM_PROCESSOR

It is not correct to do so, because ARCH should only take values
supported by the -march argument, with the exception of 'default'
which denotes not passing -march at all.

ARCH defines the target architecture for builds that are intended to be
portable to other machines.
This commit is contained in:
redfish 2016-08-28 01:37:34 -04:00
parent a569b264bc
commit c54b9a1a05

View File

@ -45,31 +45,26 @@ function (die msg)
message(FATAL_ERROR "${BoldRed}${msg}${ColourReset}") message(FATAL_ERROR "${BoldRed}${msg}${ColourReset}")
endfunction () endfunction ()
if ("${ARCH}" STREQUAL "" OR "${ARCH}" STREQUAL "native") # ARCH defines the target architecture, either by an explicit identifier or
set(ARCH ${CMAKE_SYSTEM_PROCESSOR}) # one of the following two keywords. By default, ARCH a value of 'native':
message(STATUS "Building natively on ${ARCH}") # target arch = host arch, binary is not portable. When ARCH is set to the
# string 'default', no -march arg is passed, which creates a binary that is
# portable across processors in the same family as host processor. In cases
# when ARCH is not set to an explicit identifier, cmake's builtin is used
# to identify the target architecture, to direct logic in this cmake script.
# Since ARCH is a cached variable, it will not be set on first cmake invocation.
if (NOT ARCH OR ARCH STREQUAL "" OR ARCH STREQUAL "native" OR ARCH STREQUAL "default")
set(ARCH_ID "${CMAKE_SYSTEM_PROCESSOR}")
else()
set(ARCH_ID "${ARCH}")
endif() endif()
string(SUBSTRING ${ARCH_ID} 0 5 ARM_TEST)
if (NOT "${ARCH}" STREQUAL "")
string(SUBSTRING ${ARCH} 0 3 IS_ARM)
string(TOLOWER ${IS_ARM} IS_ARM)
if (${IS_ARM} STREQUAL "arm")
string(SUBSTRING ${ARCH} 0 5 ARM_TEST)
string(TOLOWER ${ARM_TEST} ARM_TEST) string(TOLOWER ${ARM_TEST} ARM_TEST)
if (${ARM_TEST} STREQUAL "armv6") if (${ARM_TEST} STREQUAL "armv6")
set(ARM6 1) set(ARM6 1)
else()
set(ARM6 0)
endif() endif()
if (${ARM_TEST} STREQUAL "armv7") if (${ARM_TEST} STREQUAL "armv7")
set(ARM7 1) set(ARM7 1)
else()
set(ARM7 0)
endif()
endif()
endif() endif()
if(WIN32 OR ARM7 OR ARM6) if(WIN32 OR ARM7 OR ARM6)
@ -312,9 +307,9 @@ if(MSVC)
endif() endif()
include_directories(SYSTEM src/platform/msc) include_directories(SYSTEM src/platform/msc)
else() else()
set(ARCH native CACHE STRING "CPU to build for: -march value or default") set(ARCH native CACHE STRING "CPU to build for: -march value or 'default' to not pass -march at all")
# -march=armv7-a conflicts with -mcpu=cortex-a7 message(STATUS "Building on ${CMAKE_SYSTEM_PROCESSOR} for ${ARCH}")
if(ARCH STREQUAL "default" OR ARM7 OR ARM6) if(ARCH STREQUAL "default")
set(ARCH_FLAG "") set(ARCH_FLAG "")
else() else()
if(ARCH STREQUAL "x86_64") if(ARCH STREQUAL "x86_64")