https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84213
Bug ID: 84213 Summary: 521.wrf_r from SPEC 2017 fails to build (link) with LTO Product: gcc Version: 8.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: lto Assignee: unassigned at gcc dot gnu.org Reporter: jamborm at gcc dot gnu.org CC: marxin at gcc dot gnu.org Target Milestone: --- 521.wrf_r from the SPEC 2017 suite fails to link when built with -O2 -g -flto=8 (or -Ofast -g -flto=8 for that matter). The error ouput (preceeded by some warnings) of the linking step is: /tmp/cc0Dr9wPdebugobj: In function `no symbol': module_ra_HWRF.fppized.f90:(.debug_info+0xcccd2b): undefined reference to `module_ra_hwrf.eq.0_' module_ra_HWRF.fppized.f90:(.debug_info+0xcccd3f): undefined reference to `module_ra_hwrf.eq.0_' module_ra_HWRF.fppized.f90:(.debug_info+0xcccd64): undefined reference to `module_ra_hwrf.eq.1_' module_ra_HWRF.fppized.f90:(.debug_info+0xcccd78): undefined reference to `module_ra_hwrf.eq.1_' module_ra_HWRF.fppized.f90:(.debug_info+0xcccd9d): undefined reference to `module_ra_hwrf.eq.2_' module_ra_HWRF.fppized.f90:(.debug_info+0xcccdb1): undefined reference to `module_ra_hwrf.eq.2_' module_ra_HWRF.fppized.f90:(.debug_info+0xcccdd6): undefined reference to `module_ra_hwrf.eq.3_' module_ra_HWRF.fppized.f90:(.debug_info+0xcccdeb): undefined reference to `module_ra_hwrf.eq.3_' module_ra_HWRF.fppized.f90:(.debug_info+0xccce10): undefined reference to `module_ra_hwrf.eq.4_' module_ra_HWRF.fppized.f90:(.debug_info+0xccce25): undefined reference to `module_ra_hwrf.eq.4_' module_ra_HWRF.fppized.f90:(.debug_info+0xccce4a): undefined reference to `module_ra_hwrf.eq.5_' module_ra_HWRF.fppized.f90:(.debug_info+0xccce5f): undefined reference to `module_ra_hwrf.eq.5_' /tmp/cc0Dr9wPdebugobj: In function `no symbol': module_ra_gfdleta.fppized.f90:(.debug_info+0xd08147): undefined reference to `module_ra_gfdleta.eq.0_' module_ra_gfdleta.fppized.f90:(.debug_info+0xd0815b): undefined reference to `module_ra_gfdleta.eq.0_' module_ra_gfdleta.fppized.f90:(.debug_info+0xd08180): undefined reference to `module_ra_gfdleta.eq.1_' module_ra_gfdleta.fppized.f90:(.debug_info+0xd08194): undefined reference to `module_ra_gfdleta.eq.1_' module_ra_gfdleta.fppized.f90:(.debug_info+0xd081b9): undefined reference to `module_ra_gfdleta.eq.2_' module_ra_gfdleta.fppized.f90:(.debug_info+0xd081cd): undefined reference to `module_ra_gfdleta.eq.2_' module_ra_gfdleta.fppized.f90:(.debug_info+0xd081f2): undefined reference to `module_ra_gfdleta.eq.3_' module_ra_gfdleta.fppized.f90:(.debug_info+0xd08207): undefined reference to `module_ra_gfdleta.eq.3_' module_ra_gfdleta.fppized.f90:(.debug_info+0xd0822c): undefined reference to `module_ra_gfdleta.eq.4_' module_ra_gfdleta.fppized.f90:(.debug_info+0xd08241): undefined reference to `module_ra_gfdleta.eq.4_' module_ra_gfdleta.fppized.f90:(.debug_info+0xd08266): undefined reference to `module_ra_gfdleta.eq.5_' module_ra_gfdleta.fppized.f90:(.debug_info+0xd0827b): undefined reference to `module_ra_gfdleta.eq.5_' collect2: error: ld returned 1 exit status Trying past revisions, this seems to have been broken for a while but at least r249731 from June worked and built the benchmark with LTO fine. I'll try to bisect.