Thanks a lot!
This made me understand that I should add -mfpu=fpv5-d16 BEFORE the comma separated linker options started with -Wl.
Then it links.
Thanks again!


1>  c:\gnuarm2017q4/bin/arm-none-eabi-g++.exe -o Debug/LedBlinkHardFp.elf -mfpu=fpv5-d16 -Wl,-gc-sections,--verbose --specs=nano.specs  -TC:\Users\DLarsen2\AppData\Local\VisualGDB\EmbeddedBSPs\arm-eabi\com.sysprogs.arm.stm32/STM32F7xxxx/LinkerScripts/STM32F769NI_flash.lds  -mcpu=cortex-m7 -mthumb -mfloat-abi=hard   -Wl,--start-group Debug/startup_stm32f769xx.o Debug/stm32f7xx_hal.o Debug/stm32f7xx_hal_adc.o Debug/stm32f7xx_hal_adc_ex.o Debug/stm32f7xx_hal_can.o Debug/stm32f7xx_hal_cec.o Debug/stm32f7xx_hal_cortex.o Debug/stm32f7xx_hal_crc.o Debug/stm32f7xx_hal_crc_ex.o Debug/stm32f7xx_hal_cryp.o Debug/stm32f7xx_hal_cryp_ex.o Debug/stm32f7xx_hal_dac.o Debug/stm32f7xx_hal_dac_ex.o Debug/stm32f7xx_hal_dcmi.o Debug/stm32f7xx_hal_dcmi_ex.o Debug/stm32f7xx_hal_dfsdm.o Debug/stm32f7xx_hal_dma.o Debug/stm32f7xx_hal_dma2d.o Debug/stm32f7xx_hal_dma_ex.o Debug/stm32f7xx_hal_dsi.o Debug/stm32f7xx_hal_eth.o Debug/stm32f7xx_hal_flash.o Debug/stm32f7xx_hal_flash_ex.o Debug/stm32f7xx_hal_gpio.o Debug/stm32f7xx_hal_hash.o Debug/stm32f7xx_hal_hash_ex.o Debug/stm32f7xx_hal_hcd.o Debug/stm32f7xx_hal_i2c.o Debug/stm32f7xx_hal_i2c_ex.o Debug/stm32f7xx_hal_i2s.o Debug/stm32f7xx_hal_irda.o Debug/stm32f7xx_hal_iwdg.o Debug/stm32f7xx_hal_jpeg.o Debug/stm32f7xx_hal_lptim.o Debug/stm32f7xx_hal_ltdc.o Debug/stm32f7xx_hal_ltdc_ex.o Debug/stm32f7xx_hal_mdios.o Debug/stm32f7xx_hal_nand.o Debug/stm32f7xx_hal_nor.o Debug/stm32f7xx_hal_pcd.o Debug/stm32f7xx_hal_pcd_ex.o Debug/stm32f7xx_hal_pwr.o Debug/stm32f7xx_hal_pwr_ex.o Debug/stm32f7xx_hal_qspi.o Debug/stm32f7xx_hal_rcc.o Debug/stm32f7xx_hal_rcc_ex.o Debug/stm32f7xx_hal_rng.o Debug/stm32f7xx_hal_rtc.o Debug/stm32f7xx_hal_rtc_ex.o Debug/stm32f7xx_hal_sai.o Debug/stm32f7xx_hal_sai_ex.o Debug/stm32f7xx_hal_sd.o Debug/stm32f7xx_hal_sdram.o Debug/stm32f7xx_hal_smartcard.o Debug/stm32f7xx_hal_smartcard_ex.o Debug/stm32f7xx_hal_spdifrx.o Debug/stm32f7xx_hal_spi.o Debug/stm32f7xx_hal_sram.o Debug/stm32f7xx_hal_tim.o Debug/stm32f7xx_hal_tim_ex.o Debug/stm32f7xx_hal_uart.o Debug/stm32f7xx_hal_usart.o Debug/stm32f7xx_hal_wwdg.o Debug/stm32f7xx_ll_fmc.o Debug/stm32f7xx_ll_sdmmc.o Debug/stm32f7xx_ll_usb.o Debug/LEDBlink.o Debug/system_stm32f7xx.o     -Wl,--end-group
1>  GNU ld (GNU Tools for Arm Embedded Processors 7-2017-q4-major) 2.29.51.20171128




-----Original Message-----
From: <email address hidden> [mailto:<email address hidden>] On Behalf Of Thomas Preud'homme
Sent: Friday, February 09, 2018 12:44 PM
To: Dag Midling Larsen <email address hidden>
Subject: [Ext] [Bug 1748410] Re: GNU arm embedded toolchain 7-2017-q4 does not resolve linking to correct standard libraries when compiling for hardware floating point .

Hi,

The output you have when using -print-multi-directory shows that the compiler would select a hardfloat multilib *if* the same options are passed when linking. The same options needs to be passed to GCC both when compiling and when linking. When compiling it ensures the files are actually compiled with floating-point instructions. When linking it ensures the linker is passed the corresponding multilib.

Best regards.

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Title:
  GNU arm embedded toolchain 7-2017-q4 does not resolve linking to
  correct standard libraries when compiling for hardware floating point
  .

Status in GNU Arm Embedded Toolchain:
  New

Bug description:
  Hi

  I'm using these compiler flags.
  -mcpu=cortex-m7 -mthumb -mfloat-abi=hard

  Then adding --verbose to the linker options shows that the linker does
  not pick the correct libraries (not using libraries in the "hard"
  folders).

  Best Regards,
  Dag

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