[llvm-bugs] [Bug 26317] New: Option -fno-math-builtin reported by -help, but not supported by clang driver

[via llvm-bugs]

https://llvm.org/bugs/show_bug.cgi?id=26317

            Bug ID: 26317
           Summary: Option -fno-math-builtin reported by -help, but not
                    supported by clang driver
           Product: clang
           Version: trunk
          Hardware: PC
                OS: Linux
            Status: NEW
          Severity: normal
          Priority: P
         Component: Driver
          Assignee: unassignedclangbugs at nondot.org
          Reporter: jeremy.bennett at embecosm.com
                CC: llvm-bugs at lists.llvm.org
    Classification: Unclassified

Created attachment 15719
  --> https://llvm.org/bugs/attachment.cgi?id=15719&action=edit
Example program from source tree attached for convenience

clang --help reports -fno-math-builtin as one of its options:

  -fno-math-builtin       Disable implicit builtin knowledge of math functions

However the option is not. Taking the clang test test/CodeGen/nomathbuiltin.c
(attached for convenience), we run:

  $ clang -fno-math-builtin -c nomathbuiltin.c 
  clang-3.9: warning: argument unused during compilation: '-fno-math-builtin'

This appears to be an option for CC1 only:

  $ clang -cc1 -fno-math-builtin nomathbuiltin.c

Works without error. The option should either be removed from the list reported
by clang --help, or be promoted to be accepted by the top level clang driver
(which would seem more consistent).

Issue identified with commit 7506929a38783ed7038f893c8f1f59f6a4ccfd20,
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@258290
91177308-0d34-0410-b5e6-96231b3b80d8

-- 
You are receiving this mail because:
You are on the CC list for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-bugs/attachments/20160126/d528b8bb/attachment.html>