tags: floor riscv64 and loongarch64 at glibc 2.17 like every other arch

CHANGELOG.md

@@ -9,6 +9,36 @@ mistaken for a safe patch upgrade.
 
 ## [Unreleased]
 
+### Fixed
+
+- `tags`: `riscv64` and `loongarch64` targets now claim the same manylinux
+  series as every other non-x86 architecture — floored at glibc 2.17, with the
+  `manylinux2014_<arch>` legacy alias — matching pypa/packaging.
+
+  These two architectures were inherited from uv's floor table, which floors
+  them at glibc 2.31 and 2.36 respectively and records no legacy alias for
+  either. Because a target below its floor claims no manylinux tag **at all**
+  rather than a shortened list, the effect was not marginal: a `loongarch64`
+  host on glibc 2.35 (Loongnix, Debian — a real configuration) was offered 42
+  tags where packaging 26.2 computes 582, so no manylinux wheel whatsoever.
+  `riscv64` on glibc 2.28 gave 42 against 393. Both figures now match packaging
+  exactly.
+
+  Both causes had to be fixed together: raising the floor alone leaves the alias
+  missing, because packaging's legacy map is keyed by glibc version *alone* and
+  is therefore architecture-independent.
+
+  Callers that compile a target for either architecture will now accept
+  manylinux wheels they previously rejected. That is the point — this package
+  answers "is this wheel installable on the declared target", and being narrower
+  than pip means rejecting wheels pip would install. For a mirror or an offline
+  bundle that shows up as silently omitted content the client cannot then
+  obtain.
+
+  `TestLinux_NarrowNonX86Floors`, which pinned the old narrow output, is
+  replaced by `TestLinux_NonX86FloorsAreUniform`, a parity assertion against
+  `aarch64` that holds as the manylinux series grows.
+
 ## [0.8.0] - 2026-08-19
 
 ### Breaking

tags/doc.go

@@ -31,27 +31,6 @@
 //     with macOS 11, so as a *declared* target that combination can only be a
 //     mistake.
 //
-//   - riscv64 and loongarch64 targets get NARROWER manylinux coverage than
-//     packaging, and the gap is large. Two independent causes, both in
-//     manylinuxFloor: this package floors those architectures at glibc 2.31 and
-//     2.36 respectively (uv's values) where packaging floors every non-x86
-//     architecture at 2.17; and it records no legacy alias for them, where
-//     packaging's legacy map is keyed by glibc version ALONE and is therefore
-//     architecture-independent, so pip does emit manylinux2014_riscv64 and
-//     manylinux2014_loongarch64. Fixing only the floor number would still not
-//     produce the alias.
-//
-//     Because a target below its floor yields no manylinux tag at all rather
-//     than a shortened list, the effect is not marginal. Measured against
-//     packaging 26.2 for a CPython 3.12 target, in order: loongarch64 on glibc
-//     2.35 gives packaging 582 tags and this package 42, missing 540;
-//     riscv64 on glibc 2.28 gives 393 against 42. glibc 2.35 loongarch64 is a
-//     real configuration (Loongnix, Debian), and such a host would be offered no
-//     manylinux wheel whatsoever. The current behavior is pinned by
-//     TestLinux_NarrowNonX86Floors so that changing the floors is a deliberate
-//     test update; those tags are not otherwise covered by the golden fixtures,
-//     since a generated fixture would record packaging's wider answer.
-//
 //   - The exact ABI of a pre-3.3 CPython target always carries the UCS-4 "u"
 //     flag, e.g. cp27mu, whatever OS the target names.
 //

tags/generate.go

@@ -321,20 +321,26 @@ type legacyManylinuxAlias struct {
 
 // manylinuxFloor is the oldest glibc version (major, minor) a given
 // architecture's manylinux tags may claim, plus any legacy aliases that
-// architecture supports. Values are uv's (github.com/astral-sh/uv) floor table,
-// which matches pypa/packaging for x86_64/i686/aarch64/armv7l/ppc64/ppc64le/
-// s390x but floors riscv64 at 2.31 and loongarch64 at 2.36.
+// architecture supports. Every non-x86 architecture floors at glibc 2.17 and
+// carries the manylinux2014 alias, matching pypa/packaging.
 //
-// ⚠️ Those last two are NARROWER than pypa/packaging 26.2, which floors every
-// non-x86 architecture at glibc 2.17 and does list both in its _ALLOWED_ARCHS
-// (verified against the installed 26.2; an earlier version of this comment
-// claimed packaging did not recognize them at all, which is no longer true, if
-// it ever was). So a riscv64 or loongarch64 target here declines manylinux tags
-// between 2.17 and its floor that pip on the same host would accept. That is a
-// real divergence on real architectures, inherited from #18632, and is
-// deliberately left alone here rather than changed as a drive-by: it is the
-// opposite direction from the cross-major fix below and deserves its own
-// decision. Tracked for follow-up.
+// This table began as uv's (github.com/astral-sh/uv) floor table, which agrees
+// with packaging for x86_64/i686/aarch64/armv7l/ppc64/ppc64le/s390x but floors
+// riscv64 at 2.31 and loongarch64 at 2.36 and records no legacy alias for
+// either. Those two entries have been widened to packaging's values, because a
+// target below its floor claims no manylinux tag AT ALL rather than a shortened
+// list: a loongarch64 host on glibc 2.35 (Loongnix, Debian -- a real
+// configuration) was offered 42 tags where pip computes 582, so no manylinux
+// wheel whatsoever. Both fixes are needed together; the floor number alone
+// leaves the alias missing, since packaging's legacy map is keyed by glibc
+// version ALONE and is therefore architecture-independent.
+//
+// Direction matters for the consumers: this package answers "is this wheel
+// installable on the declared target", and the thing that ultimately installs
+// is pip. Being NARROWER than pip rejects wheels pip would accept, which for a
+// mirror or an offline bundle means silently omitting content the client then
+// cannot get. Being wider only costs bytes. Where the two upstreams disagree,
+// follow the one pip uses.
 //
 // Rule (Global Constraints): a target declaring glibc (2, m) accepts a
 // manylinux_2_y tag iff m >= y, down to this floor.
@@ -348,16 +354,13 @@ var manylinuxFloor = map[string]struct {
 	"i686": {2, 5, []legacyManylinuxAlias{
 		{"manylinux1", 2, 5}, {"manylinux2010", 2, 12}, {"manylinux2014", 2, 17},
 	}},
-	"aarch64": {2, 17, []legacyManylinuxAlias{{"manylinux2014", 2, 17}}},
-	"armv7l":  {2, 17, []legacyManylinuxAlias{{"manylinux2014", 2, 17}}},
-	"ppc64":   {2, 17, []legacyManylinuxAlias{{"manylinux2014", 2, 17}}},
-	"ppc64le": {2, 17, []legacyManylinuxAlias{{"manylinux2014", 2, 17}}},
-	"s390x":   {2, 17, []legacyManylinuxAlias{{"manylinux2014", 2, 17}}},
-	"riscv64": {2, 31, nil},
-	// loongarch64's floor is uv's 2.36. pypa/packaging 26.2 does recognize this
-	// architecture -- it is in _ALLOWED_ARCHS -- but floors it at 2.17 like
-	// every other non-x86 arch; see the divergence note above.
-	"loongarch64": {2, 36, nil},
+	"aarch64":     {2, 17, []legacyManylinuxAlias{{"manylinux2014", 2, 17}}},
+	"armv7l":      {2, 17, []legacyManylinuxAlias{{"manylinux2014", 2, 17}}},
+	"ppc64":       {2, 17, []legacyManylinuxAlias{{"manylinux2014", 2, 17}}},
+	"ppc64le":     {2, 17, []legacyManylinuxAlias{{"manylinux2014", 2, 17}}},
+	"s390x":       {2, 17, []legacyManylinuxAlias{{"manylinux2014", 2, 17}}},
+	"riscv64":     {2, 17, []legacyManylinuxAlias{{"manylinux2014", 2, 17}}},
+	"loongarch64": {2, 17, []legacyManylinuxAlias{{"manylinux2014", 2, 17}}},
 }
 
 // linuxPlatformTags builds the ordered platform-tag list for a linux
@@ -429,8 +432,8 @@ type glibcVersion struct {
 //     will stop.
 //
 // Within the floor's own major the walk bottoms out at that architecture's floor
-// minor from manylinuxFloor -- 2.5 on x86_64/i686, 2.17 on most others, but 2.31
-// on riscv64 and 2.36 on loongarch64; any other major goes down to <major>_0.
+// minor from manylinuxFloor -- 2.5 on x86_64/i686, 2.17 on every other
+// architecture; any other major goes down to <major>_0.
 //
 // So "below the floor" has two different answers, and conflating them is how this
 // function's narrower predecessor looked correct:

tags/target_test.go

@@ -199,56 +199,54 @@ func TestLinux_CrossGlibcMajor(t *testing.T) {
 	})
 }
 
-// TestLinux_NarrowNonX86Floors pins the riscv64/loongarch64 manylinux
-// divergence documented in doc.go. It asserts THIS PACKAGE'S current, narrower
-// output rather than upstream's, which is why it is hand-written instead of a
-// generated golden fixture: a fixture from packaging would record the wider
-// answer and fail.
+// TestLinux_NonX86FloorsAreUniform asserts that every non-x86 architecture
+// claims the same manylinux series as every other, i.e. floors at glibc 2.17
+// and carries the manylinux2014 alias, matching pypa/packaging.
 //
-// It exists so that changing manylinuxFloor is a deliberate test update rather
-// than silent drift, and so the size of the gap is written down somewhere
-// executable. Measured against packaging 26.2 for these same targets, in order:
-// loongarch64/glibc 2.35 gives packaging 582 tags to our 42, and
-// riscv64/glibc 2.28 gives 393 to our 42.
+// riscv64 and loongarch64 used to be the exceptions: inherited from uv's floor
+// table, they floored at 2.31 and 2.36 with no legacy alias. Because a target
+// below its floor claims no manylinux tag AT ALL rather than a shortened list,
+// that was not marginal -- a loongarch64 host on glibc 2.35 got 42 tags where
+// packaging computes 582, so no manylinux wheel whatsoever.
 //
-// If you are here because you widened the floors to 2.17 and this test failed:
-// that is the intended interaction. Update the expectations, and add the legacy
-// alias too -- packaging's legacy map is keyed by glibc version alone, so
-// manylinux2014_<arch> applies to these architectures despite manylinuxFloor
-// recording no alias for them.
-func TestLinux_NarrowNonX86Floors(t *testing.T) {
-	for _, tc := range []struct {
-		arch                 string
-		libcMajor, libcMinor int
-		upstreamTagCount     int
-	}{
-		{"loongarch64", 2, 35, 582},
-		{"riscv64", 2, 28, 393},
-	} {
-		t.Run(tc.arch, func(t *testing.T) {
-			m, err := Target{
-				Implementation: "cp", PyMajor: 3, PyMinor: 12,
-				OS: "linux", Arch: tc.arch,
-				Libc: "glibc", LibcMajor: tc.libcMajor, LibcMinor: tc.libcMinor,
-			}.Compile()
-			require.NoError(t, err)
-			ss := tagStrings(m.Tags())
+// This is written as a PARITY assertion against a reference architecture rather
+// than as a hardcoded tag list on purpose: it is the actual invariant, and it
+// keeps holding when the manylinux series is extended. Re-narrowing any single
+// architecture breaks it, which is what the old pinning test was for.
+func TestLinux_NonX86FloorsAreUniform(t *testing.T) {
+	// Platform tags for arch at a fixed glibc, with the architecture suffix
+	// normalized away so two architectures' series can be compared directly.
+	seriesFor := func(t *testing.T, arch string) []string {
+		t.Helper()
+		m, err := Target{
+			Implementation: "cp", PyMajor: 3, PyMinor: 12,
+			OS: "linux", Arch: arch,
+			Libc: "glibc", LibcMajor: 2, LibcMinor: 35,
+		}.Compile()
+		require.NoError(t, err)
+
+		var out []string
+		for _, tag := range m.Tags() {
+			out = append(out, strings.ReplaceAll(tag.Platform, arch, "<arch>"))
+		}
+		return out
+	}
+
+	// aarch64 was never affected, so it is the reference for what a non-x86
+	// architecture should claim.
+	want := seriesFor(t, "aarch64")
 
-			// Below its floor this target claims no manylinux tag at all -- not
-			// a shortened list -- so the only platform tag left is the bare one.
-			for _, s := range ss {
-				assert.NotContains(t, s, "manylinux",
-					"%s glibc %d.%d is below its floor and must claim no manylinux tag",
-					tc.arch, tc.libcMajor, tc.libcMinor)
-			}
-			assert.Contains(t, ss, "cp312-cp312-linux_"+tc.arch)
+	// Guard the reference itself, so a regression there cannot make the parity
+	// assertions below vacuously pass.
+	require.Contains(t, want, "manylinux_2_17_<arch>",
+		"reference architecture must reach the 2.17 floor")
+	require.Contains(t, want, "manylinux2014_<arch>",
+		"reference architecture must carry the legacy alias")
 
-			// The magnitude of the divergence, recorded executably. 42 is the
-			// bare-linux-only tag count; upstreamTagCount is what packaging 26.2
-			// produces for the same target.
-			assert.Len(t, ss, 42)
-			assert.Less(t, len(ss), tc.upstreamTagCount,
-				"this package is narrower than packaging here, by design but not by preference")
+	for _, arch := range []string{"riscv64", "loongarch64", "armv7l", "ppc64", "ppc64le", "s390x"} {
+		t.Run(arch, func(t *testing.T) {
+			assert.Equal(t, want, seriesFor(t, arch),
+				"%s must claim the same manylinux series as aarch64", arch)
 		})
 	}
 }