Closed
Description
Original report: japaric/stm32f103xx-hal#44
STR
$ git clone https://github.com/japaric/stm32f103xx-hal
$ cd stm32f103xx-hal
$ git checkout 9f80811a6026f0849ce2afee5baf0cf086563b65
$ xargo build --example reactive-serial-circ --release
(..)
Finished release [optimized + debuginfo] target(s) in 13.52 secs
(..)
Finished release [optimized + debuginfo] target(s) in 2.24 secs
(..)
Finished release [optimized + debuginfo] target(s) in 38.37 secs
$ arm-none-eabi-size target/thumbv7m-none-eabi/release/examples/reactive-serial-circ
text data bss dec hex filename
12154 8 20 12182 2f96 (..)
$ xargo bloat --example reactive-serial-circ --release
File .text Size Name
0.0% 2.3% 170B [15 Others]
0.4% 18.9% 1.4KiB core::fmt::Formatter::pad_integral
0.2% 12.9% 962B core::fmt::Formatter::pad
0.2% 9.7% 720B stm32f103xx_hal::rcc::CFGR::freeze
0.2% 9.0% 672B core::str::slice_error_fail
0.1% 7.3% 544B core::fmt::write
0.1% 7.2% 538B <char as core::fmt::Debug>::fmt
0.1% 5.9% 440B _ZN20reactive_serial_circ4main17h416bbf939f973349E.llvm.E85F65E9
0.1% 4.6% 340B cortex_m::peripheral::nvic::<impl cortex_m::peripheral::NVIC>::enable
0.1% 3.6% 266B _ZN4core3fmt10ArgumentV110show_usize17h636fea4f06967745E.llvm.EA6B2883
0.1% 3.6% 266B core::fmt::num::<impl core::fmt::Display for usize>::fmt
0.1% 3.6% 266B core::fmt::num::<impl core::fmt::Debug for usize>::fmt
0.0% 2.4% 182B _ZN4core12char_private5check17h7f91014bbb6a3313E.llvm.9871CEB7
0.0% 1.6% 118B DMA1_CHANNEL5
0.0% 1.4% 106B cortex_m_rt::reset_handler
0.0% 1.2% 92B core::result::unwrap_failed
0.0% 1.0% 78B core::slice::slice_index_order_fail
0.0% 1.0% 78B core::slice::slice_index_len_fail
0.0% 1.0% 74B core::panicking::panic_bounds_check
0.0% 0.9% 70B <core::ops::range::Range<Idx> as core::fmt::Debug>::fmt
0.0% 0.8% 60B core::panicking::panic
1.9% 100.0% 7.3KiB .text section size, the file size is 376.2KiBChanging profile.release.codegen-units to 1 (suggested in other issues) does not help. Fully
disabling ThinLTO passing -Z thinlto=no to rustc (is there a Cargo.toml setting for that?) fixes
the binary size problem without meaningfully affecting the compilation speed (if anything it's
slightly faster)
$ cat .cargo/config
[target.thumbv7m-none-eabi]
runner = 'arm-none-eabi-gdb'
rustflags = [
"-C", "link-arg=-Tlink.x",
"-C", "linker=arm-none-eabi-ld",
"-Z", "linker-flavor=ld",
"-Z", "thinlto=no", # <-
]
[build]
target = "thumbv7m-none-eabi"
$ xargo build --example reactive-serial-circ --release
(..)
Finished release [optimized + debuginfo] target(s) in 12.69 secs
(..)
Finished release [optimized + debuginfo] target(s) in 1.98 secs
(..)
Finished release [optimized + debuginfo] target(s) in 38.54 secs
$ arm-none-eabi-size target/thumbv7m-none-eabi/release/examples/reactive-serial-circ
text data bss dec hex filename
890 8 20 918 396 (..)
$ xargo bloat --example reactive-serial-circ --release
File .text Size Name
0.0% 0.0% 0B [0 Others]
0.1% 37.2% 250B reactive_serial_circ::init
0.1% 29.2% 196B cortex_m_rt::reset_handler
0.0% 16.1% 108B DMA1_CHANNEL5
0.0% 1.5% 10B core::result::unwrap_failed
0.0% 1.5% 10B SVCALL
0.0% 1.5% 10B MEM_MANAGE
0.0% 1.5% 10B DEBUG_MONITOR
0.0% 1.5% 10B PENDSV
0.0% 1.5% 10B USAGE_FAULT
0.0% 1.5% 10B SYS_TICK
0.0% 1.5% 10B NMI
0.0% 1.5% 10B DEFAULT_HANDLER
0.0% 1.5% 10B BUS_FAULT
0.0% 1.5% 10B HARD_FAULT
0.0% 0.6% 4B core::panicking::panic_fmt
0.0% 0.6% 4B cortex_m_rt::default_handler
0.3% 100.0% 672B .text section size, the file size is 261.6KiBMeta
$ rustc -Vv
rustc 1.25.0-nightly (ae920dcc9 2018-01-22)Given the severity of the issue I'm going to recommend my users to disable ThinLTO as I already do
with parallel codegen and incremental compilation.
cc @alexcrichton @aturon
cc #47745