Introduce ESPTOOLPY_FAST_REFLASHING configuration option. It instructs
ldgen to group entity mappings for libraries deemed mutable (prone to
change) separately from those considered immutable (unlikely to change).
Organizing mutable and immutable libraries separately in the linker
script allows the linker to form larger contiguous blocks of data for
immutable libraries in the application's output sections. These blocks
are likely to stay mostly unchanged between application recompilations,
enabling them to be skipped during reflashing.
Separating mutable and immutable libraries in the linker script to
minimize changes in the output sections is insufficient. Padding is
added after the input sections of mutable libraries in the default data
and text output sections. This creates a buffer for the mutable
libraries, allowing additional changes to be made without altering the
layout of the binary image.
Additionally two optimizations currently in use can still mix data from
these libraries, leading to significant changes even within the grouped
immutable libraries.
1. constant merging
Linker will try to merge input sections that have the MERGE and
STRING flags from different libraries (object files) to perform
optimizations like tail merging. For example, adding a string
literal in a mutable library will also change the addresses of
string literals from immutable libraries in such a merged section,
causing changes in the generated code when those literals are
referenced.
Disabled with COMPILER_DISABLE_MERGE_CONSTANTS(-fno-merge-constants)
2. literal pools on Xtensa
As optimization, the linker may merge literal pools from different
libraries (object files) to improve the generated code size. This
has the same effect as constant merging, and changes in mutable
libraries may cause changes in the generated code for immutable
libraries. To get larger unchanged continuous blocks in the text
output sections for immutable libraries, we need to ensure that the
Xtensa literal pools remain close to their references and are not
merged.
Disabled with CONFIG_COMPILER_ENABLE_TEXT_SECTION_LITERALS(-mtext-section-literals)
When ESPTOOLPY_FAST_REFLASHING is enabled, these two optimizations are
disabled to achieve larger unchaged continuous blocks for the grouped
immutable libraries, even though disabling these optimizations results
in slightly larger code.
Signed-off-by: Frantisek Hrbata <frantisek.hrbata@espressif.com>
There are idf.py hints for helping the user to set component
dependencies properly instead of building sources out-of-component or
including headers from outside the component directory. These are
produced with
tools/idf_py_actions/hint_modules/component_requirements.py.
However, idf.py hints are printed only when the build fails. If the user
starts with a buildable solution then the suggestions to add component
dependencies are not printed.
This commit introduces cmake-level warnings for building source files
from outside the component and including header files without setting up
proper component dependencies.
Allow to disable implicit inlining of constexpr functions from libstdc++.
This is a known GCC issue https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93008
that may affect C++ application size depending on its structure.
GCC defines that malloc(0) returns a non-null pointer (glibc behavior).
This can break logic for some cases, because our implementation of
malloc(0) returns null pointer.
POSIX and the ISO C standard allow both behaviors.
GCC 15 introduces a regression in guaranteed zero-initialization of
padding bits. The suggested solution is to add the
-fzero-init-padding-bits=unions compile option.
To prevent similar issues in the future, this change adds the
-fzero-init-padding-bits=all build option. It ensures that padding bits
in unions and structs are properly zeroed, avoiding regressions.
See https://clang.llvm.org/docs/CommandGuide/clang.html:
>> Code Generation Options
>> -Oz Like -Os (and thus -O2), but reduces code size further.
Without -Oz enabled clang produced binaries that were too large.
This commit updates the ld linker flags to conditionally include the
-warn_commons flag when the linux target is built on MacOS. This is
because, not all versions of ld support the -warn_commons option.
Closes https://github.com/espressif/esp-idf/issues/13185
Probably GCC-13.x and on-wards uses "-fmerge-constants" to merge
the const section (string/floating-point) across compilation units.
This makes it difficult to properly analyze the size output of rodata
section across libraries, the merged section (big in size) is showed
across a single library.
The config option added here can help to disable this compiler behavior
and help to provide better size analysis. It can be used during
development phase only as it increases rodata section size.
The -Werror=all activates error for all warnings in -Wall, however, it
does not activate error for other default warnings, such as:
- int-conversion (pointer from integer w/o a cast)
- incompatible-pointer-types
- discarded-qualifiers
Which are IMO even more important that -Wall.
This commit fixes that by activating error for all warnings (i.e. from
-Wall and default ones) and removing those from -Wextra, as the culprit
commit seemed to address.
Fixes: 60f29236f6 "Build system: Raise warning level" (2016-11-16)
In order to avoid long analysis during esp-idf upgrade, provide a way to
restore the previous -Werror=all behavior that consider only warnings
from -Wall (and not default ones).
Also add a hint to use the Kconfig option on compilation error, but warn
that fixing the code is the preferred way.
Merges https://github.com/espressif/esp-idf/pull/11239
Suggested-By: Ivan Grokhotkov <ivan@espressif.com>
This updates the minimal supported version of CMake to 3.16, which in turn enables us to use more CMake features and have a cleaner build system.
This is the version that provides most new features and also the one we use in our latest docker image for CI.
This commit updates the usage of idle hooks in SMP FreeRTOS as follows:
- IDF style idle hooks are now called from vApplicationMinimalIdleHook()
- If the user provdies their own vApplicationMinimalIdleHook(), it can be
wrapped using -Wl,--wrap if CONFIG_FREERTOS_USE_MINIMAL_IDLE_HOOK is
enabled.
- SMP port no longer uses vApplicationIdleHook() as it's only called from
the prvIdleTask() and not every prvMinimalIdleTask()
Clang outputs performance warnings by default for atomic operations with
access size more then 4 bytes. So add "-Wno-atomic-alignment add" flag to
ESP-IDF cmake script.
GCC since version 10 uses -fno-common by default and will not emit
common symbols. Enable this option to find the occurrences of common
symbols in ESP-IDF.
Closes https://github.com/espressif/esp-idf/issues/5080
When building for "linux" (~POSIX) target on macOS, the system linker
is normally used. MacOS linker doesn't recognise --gc-sections, but
has a -dead_strip flag which is equivalent.
To make the transition from 32-bit time_t to 64-bit time_t smoother,
detect the size of this type in CMake and remove the manual option in
Kconfig.
The information about 64-bit time_t support is moved from Kconfig help
string into the "system time" section of the API reference.
Defining CMake variables from the command-line or from another CMake project,
such as `-DCMAKE_C_FLAGS= -DCMAKE_CXX_FLAGS=`, caused a link failure as ESP
CMake was unable to set its proper compilation flags.
Additional CMake compiler flags can now be provided by another project.
* Closes https://github.com/espressif/esp-idf/issues/7507
Alexey Lapshin
Frantisek Hrbata
Jakub Kocka
Alexey Gerenkov
Roland Dobai
Deomid rojer Ryabkov
Marek Fiala
Marius Vikhammer
Chen Jichang
Omar Chebib
Laukik Hase
Alexey Storozhev
Sudeep Mohanty
Ivan Grokhotkov
Mahavir Jain
Konstantin Kondrashov
Marc Finet
Darian Leung
radek.tandler
Djordje Nedic
Anton Maklakov
Andrei Safronov
Fu Hanxi