2056917 - [riscv64] Compilation failure on GCC 15+: declaration of ‘int js::jit::InstructionBase::BaseOpcode() const’ changes meaning of ‘BaseOpcode’

Status: RESOLVED FIXED

(Core :: JavaScript Engine: JIT, defect)

Description

[Rong Bao [:csmantle]]

When building SM/Fx targeting riscv64{,-simulator} with GCC 15.3.0 or 16.1.1, the following error occurs:

74:33.11 E /var/cache/acbs/build/acbs.gndd9uk9/firefox-153.0/js/src/jit/riscv64/base/Instruction.h:215:14: error: declaration of ‘int js::jit::InstructionBase::BaseOpcode() const’ changes meaning of ‘BaseOpcode’ [-Wchanges-meaning]
74:33.11 E 215 | inline int BaseOpcode() const { return InstructionBits() & kBaseOpcodeMask; }
74:33.12 E | ^~~~~~~~~~
74:33.13 E /var/cache/acbs/build/acbs.gndd9uk9/firefox-153.0/js/src/jit/riscv64/base/Instruction.h:133:10: note: used here to mean ‘enum js::jit::BaseOpcode’
74:33.13 E 133 | inline BaseOpcode BaseOpcodeFieldRaw() const {
74:33.14 E | ^~~~~~~~~~
74:33.14 W In file included from /var/cache/acbs/build/acbs.gndd9uk9/firefox-153.0/js/src/jit/riscv64/constant/Constant-riscv64.h:8,
74:33.15 W from /var/cache/acbs/build/acbs.gndd9uk9/firefox-153.0/js/src/jit/riscv64/base/Instruction.h:13:
74:33.16 W /var/cache/acbs/build/acbs.gndd9uk9/firefox-153.0/js/src/jit/riscv64/constant/Base-constant-riscv.h:258:6: note: declared here
74:33.16 W 258 | enum BaseOpcode : uint32_t {
74:33.17 W | ^~~~~~~~~~
74:36.87 W In file included from /var/cache/acbs/build/acbs.gndd9uk9/firefox-153.0/js/src/jit/riscv64/base/base-assembler-riscv.h:42, 

Qualifying BaseOpcode in the return type position should fix it (Compiler Explorer before, after).

Comment 1

[Rong Bao [:csmantle]]

Attachment: Bug 2056917 - [riscv64] Qualify enum BaseOpcode in return type position in InstructionBase. r=jandem!

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/0be02e974718
https://hg.mozilla.org/integration/autoland/rev/dbd09a636597
[riscv64] Qualify enum BaseOpcode in return type position in InstructionBase. r=anba

Comment 3

[Norisz Fay [:noriszfay]]

https://hg.mozilla.org/mozilla-central/rev/dbd09a636597

Comment 4

[Norisz Fay [:noriszfay]]

https://hg.mozilla.org/mozilla-central/rev/dbd09a636597

Comment 5

[Norisz Fay [:noriszfay]]

https://hg.mozilla.org/mozilla-central/rev/dbd09a636597

Comment 6

[Norisz Fay [:noriszfay]]

https://hg.mozilla.org/mozilla-central/rev/dbd09a636597

Comment 7

[Rong Bao [:csmantle]]

Attachment: Bug 2056917 - [riscv64] Qualify enum BaseOpcode in return type position in InstructionBase.

Original Revision: https://phabricator.services.mozilla.com/D313478

Comment 8

[Phabricator Automation]

firefox-beta Uplift Approval Request

• User impact if declined/Reason for urgency: Firefox would fail to build on RISC-V platforms using GCC.
• Code covered by automated testing?: no
• Fix verified in Nightly?: yes
• Needs manual QE testing?: no
• Steps to reproduce for manual QE testing: N/A.
• Risk associated with taking this patch: low
• Explanation of risk level: This is a two-line fix targeting a Tier-3 platform, so the impact is limited.
• String changes made/needed?: None.
• Is Android affected?: no

Comment 9

[Phabricator Automation]

firefox-release Uplift Approval Request

• User impact if declined/Reason for urgency: Firefox would fail to build on RISC-V platforms using GCC.
• Code covered by automated testing?: no
• Fix verified in Nightly?: yes
• Needs manual QE testing?: no
• Steps to reproduce for manual QE testing: N/A.
• Risk associated with taking this patch: low
• Explanation of risk level: This is a two-line fix targeting a Tier-3 platform, so the impact is limited.
• String changes made/needed?: None.
• Is Android affected?: no

Comment 10

[Rong Bao [:csmantle]]

Attachment: Bug 2056917 - [riscv64] Qualify enum BaseOpcode in return type position in InstructionBase.

Original Revision: https://phabricator.services.mozilla.com/D313478

Comment 11

[Pulsebot]

https://github.com/mozilla-firefox/firefox/commit/b2ede9f54c9d
https://hg.mozilla.org/releases/mozilla-beta/rev/3d898880e588

Comment 12

[Pulsebot]

https://github.com/mozilla-firefox/firefox/commit/400567e45350
https://hg.mozilla.org/releases/mozilla-release/rev/0ed799cf0ffc

Comment 13

[Pulsebot]

https://hg.mozilla.org/releases/mozilla-esr153/rev/8b43d577a229