cmd/go/internal/verylongtest: TestScript/repro_build failures

[gopherbot]

#!watchflakes
default <- pkg == "cmd/go/internal/verylongtest" && test == "TestScript/repro_build"

Issue created automatically to collect these failures.

Example (log):

=== RUN   TestScript/repro_build
=== PAUSE TestScript/repro_build
=== CONT  TestScript/repro_build
    run.go:250: 2026-04-22T21:37:53Z
    run.go:252: $WORK=/Users/swarming/.swarming/w/ir/x/t/TestScriptrepro_build1338077345/001
    run.go:259: 
        BOTO_CONFIG=/Users/swarming/.swarming/w/ir/x/a/gsutil-bbagent/.boto
        CIPD_ARCHITECTURE=amd64
        CIPD_CACHE_DIR=/Users/swarming/.swarming/w/ir/cache/cipd_cache
        CIPD_PROTOCOL=v2
...
        [condition not met]
        > [GOOS:aix] env CGO_ENABLED=0  # go.dev/issue/56896
        [condition not met]
        > env GOMAXPROCS=16
        > go build -a -o http16.o net/http
        > env GOMAXPROCS=17
        > go build -a -o http17.o net/http
        > cmp -q http16.o http17.o
    run.go:259: FAIL: testdata/script/repro_build.txt:9: cmp -q http16.o http17.o: http16.o and http17.o differ
--- FAIL: TestScript/repro_build (191.10s)

— watchflakes

[gopherbot]

Found new dashboard test flakes for:

#!watchflakes
default <- pkg == "cmd/go/internal/verylongtest" && test == "TestScript/repro_build"

2026-04-22 20:45 gotip-darwin-amd64-longtest go@be450234 cmd/go/internal/verylongtest.TestScript/repro_build (log)

=== RUN   TestScript/repro_build
=== PAUSE TestScript/repro_build
=== CONT  TestScript/repro_build
    run.go:250: 2026-04-22T21:37:53Z
    run.go:252: $WORK=/Users/swarming/.swarming/w/ir/x/t/TestScriptrepro_build1338077345/001
    run.go:259: 
        BOTO_CONFIG=/Users/swarming/.swarming/w/ir/x/a/gsutil-bbagent/.boto
        CIPD_ARCHITECTURE=amd64
        CIPD_CACHE_DIR=/Users/swarming/.swarming/w/ir/cache/cipd_cache
        CIPD_PROTOCOL=v2
...
        [condition not met]
        > [GOOS:aix] env CGO_ENABLED=0  # go.dev/issue/56896
        [condition not met]
        > env GOMAXPROCS=16
        > go build -a -o http16.o net/http
        > env GOMAXPROCS=17
        > go build -a -o http17.o net/http
        > cmp -q http16.o http17.o
    run.go:259: FAIL: testdata/script/repro_build.txt:9: cmp -q http16.o http17.o: http16.o and http17.o differ
--- FAIL: TestScript/repro_build (191.10s)

— watchflakes

[cagedmantis]

cc @golang/go-command

[prattmic]

Darwin builds have had memory issues, so this could be that. Waiting to see if it happens more or elsewhere.

[gopherbot]

Found new dashboard test flakes for:

#!watchflakes
default <- pkg == "cmd/go/internal/verylongtest" && test == "TestScript/repro_build"

2026-05-25 22:34 gotip-darwin-amd64-longtest go@9c2b47b0 cmd/go/internal/verylongtest.TestScript/repro_build (log)

=== RUN   TestScript/repro_build
=== PAUSE TestScript/repro_build
=== CONT  TestScript/repro_build
    run.go:250: 2026-05-25T23:43:38Z
    run.go:252: $WORK=/Users/swarming/.swarming/w/ir/x/t/TestScriptrepro_build2252837191/001
    run.go:259: 
        BOTO_CONFIG=/Users/swarming/.swarming/w/ir/x/a/gsutil-bbagent/.boto
        CIPD_ARCHITECTURE=amd64
        CIPD_CACHE_DIR=/Users/swarming/.swarming/w/ir/cache/cipd_cache
        CIPD_PROTOCOL=v2
...
        ../../TestScript2141553274/001/testgoroot/src/vendor/golang.org/x/text/unicode/norm/tables17.0.0.go:42:5: internal compiler error: panic: assertion failed
        
        goroutine 1 [running]:
        runtime/debug.Stack()
        	runtime/debug/stack.go:26 +0x5e
        cmd/compile/internal/base.FatalfAt({0x2a9ac00?, 0x0?}, {0x36044d0, 0x9}, {0x15be9a3de120, 0x1, 0x1})
        	cmd/compile/internal/base/print.go:232 +0x18b
        cmd/compile/internal/base.Fatalf(...)
        	cmd/compile/internal/base/print.go:197
        cmd/compile/internal/gc.handlePanic()
...
        	cmd/compile/internal/noder/unified.go:212 +0x1f9
        cmd/compile/internal/noder.LoadPackage({0x15be98a80500, 0x9, 0xa})
        	cmd/compile/internal/noder/noder.go:76 +0x529
        cmd/compile/internal/gc.Main(0x3ff4ef0)
        	cmd/compile/internal/gc/main.go:217 +0xce5
        main.main()
        	cmd/compile/main.go:57 +0x105
        
    run.go:259: FAIL: testdata/script/repro_build.txt:11: go build -a -o http18.o net/http: exit status 1
--- FAIL: TestScript/repro_build (362.92s)

— watchflakes