Why does the Altera® Advanced Link Analyzer Crash or Produce Incorrect Results on Microsoft Windows 11* 25H2 Virtual Machines?
Description The Altera® Advanced Link Analyzer may crash or produce incorrect simulation results on Microsoft® Windows 11 version 25H2 virtual machines configured with ABI‑based virtual CPU models. This problem occurs because the Intel® Math Kernel Library (MKL) depends on hardware‑faithful x86 CPU execution semantics, which are not fully guaranteed by ABI‑based vCPUs in Microsoft Windows 11 25H2. Resolution To work around this problem, you can configure virtual machines as follows: Microsoft Windows* 11 version 25H2 Use a hardware-faithful vCPU (for example, VMware ESXi* or VMware Workstation* default vCPU) On KVM/QEMU platforms, enable host CPU passthrough Microsoft Windows Server 2022, Windows Server 2025, and Windows 11 version 24H2 or earlier ABI-based virtual CPUs are supported; no changes required Additional Information This problem only affects Microsoft Windows 11 version 25H2 virtual machines using ABI‑based virtual CPU models. Other Windows versions and hardware‑faithful virtual CPUs are not affected.Why do I unexpectedly observe intermittent DDM Errors?
Description Beginning January 10, 2026, executing commands in the terminal or GUI of Quartus® Prime Pro Edition software, Quartus Embedded Edition software or select standalone tools may cause the software or tool to crash with an error similar to the crash signature shown below. This error affects: Quartus Prime Pro Software versions v23.3 through v25.3.1 Standalone Quartus Prime Pro Programmer v23.3 through v25.3.1 Standalone Quartus Prime Pro Embedded Edition v25.3 and v25.3.1 Standalone Quartus Prime Pro Power Thermal Analyzer v25.3 through v25.3.1 This issue is not observed in Quartus Prime Pro Edition versions 23.2 or prior or Quartus Prime Standard Edition. Crash Signature: Error (22912): Unhandled exception: Fatal Error: Assertion failed tools/cpp/ddm/ddm_assessor.cpp:53: DDM_T::verify_token(token) : Cannot identify the client from function assertion_error in tools/cpp/ddm_report/ddm_report_msg.cpp@465 *** Fatal Error: Program termination requested *** *** Below is the stack trace at the time the error occurred. *** The lines beginning "Err Handler" represent frames relating *** to generating this report. *** The point at which the error occurred is somewhere after these lines. *** There may be a few frames representing standard/library code *** before the Quartus frames begin. *** The search for the error should begin with the Quartus frames. *** Unwinder: libunwind *** Stack depth: 15 Quartus 0x24e67: err_terminator() + 0x1bc (ccl_err) Quartus 0xb036a: __cxxabiv1::__terminate(void (*)()) + 0xa (stdc++) Quartus 0xb03d5: (stdc++) Quartus 0xb0628: (stdc++) Quartus 0x1680d: void ddm_throw<DDM_RUNTIME_ERROR>(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) + 0x26d (ddm_report) Quartus 0x13fae: DDM_REPORT::DDM_ASSERTION_HANDLER::assertion_error(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >) const + 0xde (ddm_report) Quartus 0x12a52: DDM_REPORT::ASSERTION_HANDLER::error(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >) + 0x72 (ddm_report) Quartus 0x13e64: DDM_REPORT::detail::assert_at_line(char const*, char const*, int, char const*, ...) + 0x1b4 (ddm_report) Quartus 0x205fb0: ddm_set_lassessor(DDM_T_ASSESSOR*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) + 0x60 (ddm) Quartus 0xf4445: DMS_MANAGER::DMS_MANAGER() + 0x5c5 (dni_dms) Quartus 0xf45b2: DMS_MANAGER::get() + 0x7a (dni_dms) Quartus 0xf6db4: _GLOBAL__sub_I_dms_manager.cpp + 0x58 (dni_dms) Quartus 0x647e: (ld-linux-x86-64) Quartus 0x6568: (ld-linux-x86-64) Quartus 0x202ca: (ld-linux-x86-64) Resolution To work around this problem: For Windows machines Download and unzip the Quartus Prime Pro version zip file that matches your Quartus Prime Pro version from this KDB. Double click on the executable ending in “windows.exe”. When the GUI pops up, press Next. Note that the GUI may look slightly different depending on the version of Quartus you are using. Accept the license agreement Specify the directory where the patch needs to be applied which may be a different location than Quartus install if you have standalone tools in a different directory from your Quartus Prime Pro software installation. Keep “Allow Patch to be uninstalled” selected. Select the software in which to install the patch: The patch will install in the directory of the software or tool you have selected. You will see an uninstall directory for the patch in your software or tool folder where patch is installed; it will contain an executable to uninstall the patch if required for any reason. To confirm patch is installed, you can run quartus_sh -v or corresponding version command for your tool via command line. Alternatively, you can Open Quartus in the GUI and select Help → About Quartus Prime in the main menu. If you are opening up a standalone tool you will navigate to Help-> About <tool_name>. For the Command Line Implementation of the patch in Windows, use the following command: <patch_filename.exe> --mode unattended --installdir <your_install_directory> --accept_eula 1 --patch_to [quartus|qprogrammer|qemb|pta] # An example to patch Quartus Prime Pro Edition Software v25.3: quartus-25.3-0.27-windows.exe --mode unattended --installdir /tmp/altera_pro/25.3 --accept_eula 1 # An example to patch the Standalone Programmer for Quartus Prime Pro Software v25.3: quartus-25.3-0.27-windows.exe --mode unattended --installdir /tmp/altera_pro/25.3 --accept_eula 1 --patch_to qprogrammer For Linux machines: Download and unzip the Quartus Prime Pro version zip file that matches your Quartus Prime Pro version from this KDB. Ensure you run chmod +x on the file ending with linux.run. Run in the command line: ./<installation_patch_run_file>. When GUI pops up, press Next. Note that the GUI may look slightly different depending on the version of Quartus you are using. Accept the license agreement Specify the directory where the patch needs to be applied which may be a different location than Quartus install if you have standalone tools in a different directory from your Quartus Prime Pro software installation. Keep “Allow Patch to be uninstalled” selected. Select the software in which to install the patch: The patch will install in the directory of the software or tool you have selected. You will see an uninstall directory for the patch in your software or tool folder where patch installed; it will contain an executable to uninstall the patch if required for any reason. To confirm patch is installed, you can run ./quartus_sh -v or corresponding version command for your tool via command line. Alternatively, you can Open Quartus in the GUI and select Help → About Quartus Prime in the main menu. If you are opening up a standalone tool you will navigate to Help-> About <tool_name>. For the Command Line Implementation of the patch in Linux, use the following command: ./<patch_filename.run> --mode unattended --installdir <your_install_directory> --accept_eula 1 --patch_to [quartus|qprogrammer|qemb|pta] # An example to patch Quartus Prime Pro Edition v25.3: ./quartus-25.3-0.27-linux.run --mode unattended --installdir /tmp/altera_pro/25.3 --accept_eula 1 # An example to patch the Standalone Programmer for Quartus Prime Pro Software v25.3: ./quartus-25.3-0.27-linux.run --mode unattended --installdir /tmp/altera_pro/25.3 --accept_eula 1 --patch_to qprogrammer This problem has been fixed in Quartus® Prime Pro Edition Software version 26.1. The below table lists the patches that are available and the associated patch number. The patch zip files are attached to the KDB below: Quartus Prime Pro Edition Version Patch Number 23.3 0.52 23.4 0.70 23.4.1 1.01 24.1 0.52 24.2 0.64 24.3 0.35 24.3.1 1.29 25.1 0.36 25.1.1 1.31 25.3 0.27 25.3.1 1.02Why does the Single Floating Point Variable Streaming Reverse FFT IP produce an incorrect output when the input order is set to Natural?
Description Due to a problem in the Quartus® Prime Software version 25.3.1 and earlier, the "Natural" option for setting "Input Order" is incorrectly available for selection and unsupported when generating the FFT IP. This option is available when using the following parameters: Direction: "Reverse", Data Flow: "Variable Streaming", Representation: "Single Floating Point". Resolution This problem is scheduled to be fixed in release 26.1 of the Quartus® Prime Software with the removal of the unsupported “Natural” option. Additional Information This problem affects the FFT IP in Quartus® Prime Software versions 17.0 to 25.3.1.Why does Ashling* RiscFree* IDE for Altera FPGAs software version 25.4.1 turns compiler warnings into errors?
Description In the Ashling* RiscFree* IDE for Altera FPGAs software version 25.4.1 (31 st Oct 2025) and later, you might see compilation error related to the following errors: Implicit int types (-Werror=implicit-int) Implicit function declarations (-Werror=implicit-function-declaration) Typos in function prototypes (-Werror=declaration-missing-parameter-type) Incorrect uses of the return statement (-Werror=return-mismatch) Using pointers as integers and vice versa (-Werror=int-conversion) Type checking on pointer types (-Werror=incompatible-pointer-types) This is due to an update in GCC 14 – GNU: Certain warnings are now errors, which affects future GCC versions. For more information, Ashling* RiscFree* IDE for Altera FPGAs software version 25.3.1 (1 st August 2025) is using GCC 13.2. Ashling* RiscFree* IDE for Altera FPGAs software version 25.4.1 (31 st Oct 2025) is using GCC 15.2. Thus, Ashling* RiscFree* IDE for Altera FPGAs software version 25.4.1 (31 st Oct 2025) and future versions are affected. Note that Ashling* RiscFree* IDE for Altera FPGAs software version 25.4.1 (31 st Oct 2025) is paired with Quartus ® Prime Pro Edition software version 26.1. Resolution GNU recommends resolving all the new errors for better code quality. If necessary, you may refer to the workaround – GNU: Turning errors back into warnings. In Board Support Package Editor, add "-fpermissive" in hal.make.cflags_user_flags.How can I tell if a Raw Binary File (.rbf) is a PR Bitstream File?
Description A customer can tell if a Raw Binary File (.rbf) is a PR Bitstream File by following the information below. Resolution A PR Bitstream will start with the value 0x97566593 at offset 0x000 AND Have the value 0x5052(PR) at offset 0x00C.Why does the Fitter report that F-Tile FHT supplies must be powered, when my design does not use FHT transceivers in an Agilex® 7 FPGA F‑Tile device compiled in the Quartus® Prime Pro software version 25.3.1 and earlier?
Description Due to a bug in the Quartus® Prime Pro software version 25.3.1 and earlier, the Fitter incorrectly reports that the VCCEHT_FHT_GXF, VCCERT1_FHT_GXF, and VCCERT2_FHT_GXF supplies must be powered, even though your Agilex® 7 FPGA F-Tile device design does not use FHT transceivers. The Agilex 7 FPGA Device Family Pin Connection Guidelines documents for F-Series, I-Series, and M-Series devices states "Tie to GND if there is no FHT channel used" for the VCCEHT_FHT_GXF, VCCERT1_FHT_GXF, and VCCERT2_FHT_GXF supplies. It is safe to power down your supplies in accordance with the Agilex 7 FPGA Device Family Pin Connection Guidelines documents for F-Series, I-Series, and M-Series devices. Resolution This problem will be fixed in a future version of the Quartus Prime Pro software.Why does my Quartus® Prime Installation fail with certificate error: SSL certificate problem: unable to get local issuer certificate (curlcode 60)?
Description Due to a problem in the Quartus® Prime Installer Software, you might see the error message shown below when you click Download & Install. This happens because the certificate bundled with the Quartus® Prime Installer Software is no longer accepted by the Altera® Content Delivery Network (CDN). As a result, secure downloads initiated during the installation process cannot be verified using the outdated certificate. The issue impacts the Installer for the following versions of Quartus software: Operating System Quartus Prime Pro Installer Version(s) Quartus Std/Lite Installer Version(s) Microsoft Windows* 23.3 to 25.3.1 23.1std to 25.1std Linux* 23.3 to 23.4 23.1std The KDB workaround provided below applies to the following versions of Quartus software: Quartus Prime Pro Installer Version(s) Quartus Std/Lite Installer Version(s) KDB workaround applies to 24.3 to 25.3.1 24.1std to 25.1std Note that for all other affected versions not covered by the KDB, you cannot use the installer workaround and must download Quartus software package files individually without using the installer. Separate packages can be found in the Individual Files tab of the Quartus Software Download pages. Resolution To work around this problem, follow these steps: 1. Download and unzip the cacert.zip, which contains the cacert.pem certificate file. 2. Specify the new certificate using one of the following methods: i) Command Line Interface (CLI): Open a command prompt or terminal and run the installer with the--cacert option, pointing to the new certificate file. Windows*: qinst_<version>.exe -sp"--cacert <full path to cacert.pem>" Linux*: qinst_<version>.run -- --cacert <full path to cacert.pem> ii) Graphical User Interface (GUI): - Open the Quartus® Prime Installer, navigate to Settings, locate the CA Certificate Path, and specify the full path to the cacert.pem certificate file. - Then, click Apply > OK. This problem is scheduled to be resolved in a future release of the Quartus® Prime Installer Software.Error: Tcl error: DVR_API: List of error MSGs are {list element in braces followed by "]" instead of space
Description Due to a problem in the Quartus® Prime Pro Edition Software version 25.3.1, you might see this error when compiling your design in Design Space Explorer II. Error: Tcl error: DVR_API: List of error MSGs are {list element in braces followed by "]" instead of space (Command was: lmap panel_name [::qed_lib::rdb_util::get_report_panel_names_matching -panel_name {} -string_match {Synthesis||Logic Synthesis Stage||Partition*||*Optimization Results||Multiplier Implementations||Multiplier Implementation Report} -regexp_match {}] {::qed_lib::rdb_util::get_report_panel_str -panel_name $panel_name})} Resolution To work around this problem in the Quartus® Prime Pro Edition Software version 25.3.1, download and install patch 1.21 This problem is scheduled to be resolved in a future release of the Quartus® Prime Pro Edition Software.Error: error deleting "<path>/0001_intel_pcie_ftile_mcdma_0_gen//pcie_ed_rp/pcie.qsf": permission denied
Description Due to a problem in the Quartus® Prime Pro Edition software version 25.3.1 and earlier on a windows* 11 system, you may see the below error during generating example designs for F-tile PCIe Multichannel DMA IP for PCI Express IP. Error: error deleting "<user default temporary folder>/alt0446_17235589168751817424.dir/0001_intel_pcie_ftile_mcdma_0_gen//pcie_ed_rp/pcie.qsf": permission denied Resolution This problem is scheduled to be fixed in a future release of the Quartus Prime Pro Edition software.Why do we observe small increase in the duration of o_rx_pfc port assertion during the “PAUSE” state in the designs generated using F-Tile Ethernet Hard IP for F-Tile devices when cycles with incoming frames are padded?
Description An Ethernet design generated using F-Tile Ethernet hard IP in Quartus® Prime Pro Edition Software for F-Tile devices is showing small increase in the duration of o_rx_pfc port assertion for cycles with incoming padded frames. The slight increase in the duration of o_rx_pfc port assertion during the “PAUSE” state is due to the cycles carrying the padded data not contributing to the PAUSE time. For data rates ranging from 10G-200G, we observe an increase in the duration of 15ns for 10G and 2.5ns for 200G for each padded frame received during “PAUSE” state. 400G PFC implementation differs from other line rates so there won’t be any increase in duration of o_rx_pfc port assertion. Resolution There is no workaround and no plan to fix this problem.
