Author: Stephen Tozer Date: 2025-04-25T12:55:10+01:00 New Revision: 2dc6e98169baeb1f73036da0ea50fd828d8323d0
URL: https://github.com/llvm/llvm-project/commit/2dc6e98169baeb1f73036da0ea50fd828d8323d0 DIFF: https://github.com/llvm/llvm-project/commit/2dc6e98169baeb1f73036da0ea50fd828d8323d0.diff LOG: Revert "[Clang] Enable -fextend-lifetimes at -Og (#118026)" Reverted following several issues appearing related to fake uses, reported on the github PR. This reverts commit a9dff35ad251cd20376ab25b26d1e5394e18ff4c. Added: Modified: clang/docs/CommandGuide/clang.rst clang/docs/ReleaseNotes.rst clang/lib/Driver/ToolChains/Clang.cpp clang/test/Driver/extend-variable-liveness.c Removed: ################################################################################ diff --git a/clang/docs/CommandGuide/clang.rst b/clang/docs/CommandGuide/clang.rst index a1e738f1afec8..42aac7b25d93c 100644 --- a/clang/docs/CommandGuide/clang.rst +++ b/clang/docs/CommandGuide/clang.rst @@ -443,11 +443,8 @@ Code Generation Options :option:`-Oz` Like :option:`-Os` (and thus :option:`-O2`), but reduces code size further. - :option:`-Og` Similar to :option:`-O1`, but with slightly reduced - optimization and better variable visibility. The same optimizations are run - as at :option:`-O1`, but the ``-fextend-variable-liveness`` flag is - also set, which tries to prevent optimizations from reducing the liveness of - user variables, improving their availability when debugging. + :option:`-Og` Like :option:`-O1`. In future versions, this option might + disable diff erent optimizations in order to improve debuggability. :option:`-O` Equivalent to :option:`-O1`. diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index d1f24fb23d44d..8140f6cc708c8 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -230,10 +230,6 @@ Modified Compiler Flags - The ``-mexecute-only`` and ``-mpure-code`` flags are now accepted for AArch64 targets. (#GH125688) -- The ``-Og`` optimization flag now sets ``-fextend-variable-liveness``, - reducing performance slightly while reducing the number of optimized-out - variables. - Removed Compiler Flags ------------------------- diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp index f98cd389509cd..762f8af886920 100644 --- a/clang/lib/Driver/ToolChains/Clang.cpp +++ b/clang/lib/Driver/ToolChains/Clang.cpp @@ -7683,13 +7683,7 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA, if (Args.hasArg(options::OPT_fretain_comments_from_system_headers)) CmdArgs.push_back("-fretain-comments-from-system-headers"); - if (Arg *A = Args.getLastArg(options::OPT_fextend_variable_liveness_EQ)) { - A->render(Args, CmdArgs); - } else if (Arg *A = Args.getLastArg(options::OPT_O_Group); - A && A->containsValue("g")) { - // Set -fextend-variable-liveness=all by default at -Og. - CmdArgs.push_back("-fextend-variable-liveness=all"); - } + Args.AddLastArg(CmdArgs, options::OPT_fextend_variable_liveness_EQ); // Forward -fcomment-block-commands to -cc1. Args.AddAllArgs(CmdArgs, options::OPT_fcomment_block_commands); diff --git a/clang/test/Driver/extend-variable-liveness.c b/clang/test/Driver/extend-variable-liveness.c index 99a5409ceccea..bbfb2ece6f297 100644 --- a/clang/test/Driver/extend-variable-liveness.c +++ b/clang/test/Driver/extend-variable-liveness.c @@ -1,8 +1,7 @@ // Tests that -fextend-variable-liveness and its aliases are correctly passed -// by the driver, and are set by default at -Og. +// by the driver. // RUN: %clang -### -c %s 2>&1 | FileCheck %s --check-prefixes=CHECK,DEFAULT -// RUN: %clang -### -Og -c %s 2>&1 | FileCheck %s --check-prefixes=CHECK,ALL // RUN: %clang -fextend-variable-liveness=none -### -c %s 2>&1 | FileCheck %s --check-prefixes=CHECK,NONE // RUN: %clang -fextend-variable-liveness=this -### -c %s 2>&1 | FileCheck %s --check-prefixes=CHECK,THIS // RUN: %clang -fextend-variable-liveness=all -### -c %s 2>&1 | FileCheck %s --check-prefixes=CHECK,ALL _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
