Compiler Configuration
The following subsections describe the projects compiler options that
are available in conf/cc/cc-options.yaml
.
INCLUDE_PATHS
Additional INCLUDE_PATHS
that are not standard compiler includes.
Standard compiler includes are derived in the configure step of the compiler.
LIBRARY_PATHS
Additional LIBRARY_PATHS
that are not standard compiler library search
paths. Standard compiler library search paths are derived in the configure
step of the compiler.
LIBRARIES
Libraries that are used when linking.
CFLAGS
CFLAGS
are configured differently or the BMS application, the Operating
System and the Hardware Abstraction Layer.
common
: options are applied to all sources (BMS, OS, HAL).common_compile_only
: options are applied to all sources (BMS, OS, HAL), but only for the compile step, not for the preprocessor build steps. The build tool automatically adds that the options--gen_cross_reference_listing
,--gen_func_info_listing
,--gen_preprocessor_listing
. These options control the generation of the*.aux
,*.crl
and*.rl
files.foxbms
:CFLAGS
that should only be applied to the BMS application sources (src/app/*
).hal
:CFLAGS
that should only be applied to the generated hardware abstraction layer sources (src/hal/*
).operating_system
:CFLAGS
that should only be applied to the operating system sources (src/os/*
).
LINKFLAGS
Flags that are passed to the compiler when linking (Note: The compiler is
used as linker when run with the argument
--run_linker
). Flags here do typically not needed to be changed except
for --heap_size=0x800
,
--stack_size=0x800
or the optimization flag -oN
where N
is the
level of optimization.
HEXGENFLAGS
Flags passed to hex file generation tool armhex
(Note: hex files are only
generated when passing a node by keyword linker_script_hex
in
bld.tiprogram(..., linker_script_hex=some_node, ...)
).
NMFLAGS
Flags passed to the armnm
tool.
The armnm
tool lists the symbols contained in an object files.
Flags here do typically not needed to be changed.
Remarks
Compiler remarks help to find potential problems at an early stage of
development.
The file conf/cc/remarks.txt
allows to list remarks and how they should be
handled.
Global remarks are set in conf/cc/remarks.txt
.
Remarks are re-loaded before compiling.
Remarks can be added to a single build step as shown in
Adding command-file that includes remarks to a single build step
1def build(bld):
2 bld.stlib(
3 source=source,
4 includes=includes,
5 cflags=cflags,
6 target=target,
7 cmd_files=
8 [bld.path.find_node("path/to/some/remark/file.txt").abspath()],
9 )
Warning
If remarks should be disabled, the option --issue_remarks
needs to be
removed in conf/cc/cc-options.yaml
.
Furthermore all command files that specify remarks need to be checked and
all diagnosis related commands need to be removed or the severity level
needs to be set to --diag_remark=...
to avoid compile errors.
The default remark settings are relatively strict to avoid common mistakes. Changing them is generally not recommended.
Note
It is possible to add all kinds of compiler flags in command files, this is not only related to remarks.
Linker Output Processing
Note
Linker output validation only works if --scan_libraries
is specified.
The linker output is processed in order to validate that the correct symbols are linked into the binary.
If a symbol is defined in multiple places the linker decided which symbol to use. This is described in TI ARM assembly tools manual in section Exhaustively Read and Search Libraries.
Consider the following linker output in Linker output.
1 Linking build\bin\src\app\main\foxbms.elf
2 remark #10252-D: Symbol "_c_int00" (pulled from "src\app\main\fstartup.c.1.obj") defined in 3 places:
3 src\app\main\fstartup.c.1.obj
4 src\hal\libfoxbms-hal.a<HL_sys_startup.c.1.obj>
5 C:\ti\ccs1030\ccs\tools\compiler\ti-cgt-arm_20.2.0.LTS\lib\rtsv7R4_A_be_v3D16_eabi.lib<boot_non_cortex_m.asm.obj>
If the symbol _c_int00
should be pulled from
src/app/main/fstartup.c.1.obj
, the linking step should be treated as
successful.
If the symbol is pulled from somewhere else an error must be
generated.
To tell this to the linker output parser a json
file that indicates which
symbol should be pulled from where needs to be defined (see
Linker pulls file linker_pulls.json).
In this file use Unix-separator and specify the linked source as seen from the
build directory.
linker_pulls.json
1{
2 "_c_int00": "src/app/main/fstartup.c.1.obj"
3}
This file needs to be specified when a program is built (see
Checking the linker output to use the correct symbols).
If the symbol _c_int00
would not be pulled from
src/app/main/fstartup.c.1.obj
an error would be generated.
1def build(bld):
2 """Build the binary"""
3 source = [
4 # list sources here
5 ]
6 includes = [
7 # list include directories here
8 ]
9 linker_script = bld.path.find_node("linker_script.cmd")
10 linker_pulls = bld.path.find_node("linker_pulls.json")
11 bld.tiprogram(
12 source=source,
13 linker_script=linker_script,
14 linker_pulls=linker_pulls,
15 includes=includes,
16 target="my-app",
17 )
For implementation details see f_ti_arm_cgt.cprogram.parse_output()
.