On Thu, Dec 28, 2017 at 4:17 PM, Thomas Gleixner <t...@linutronix.de> wrote: > On Thu, 28 Dec 2017, Thomas Gleixner wrote: > > Sorry for the spam. I somehow missed to refresh the patch before generating > the mbox. Find below the correct version of that one which has ALL braces > removed which we don't need.
Hi Thomas, I'm not sure how we reached the conclusion that we should remove ALL braces? I cannot find related discussion in the archive except for the "WITH" case. This is conflicting with the current SPDX spec at https://spdx.org/spdx-specification-21-web-version quoted below and also the explenation in your own file. Quote from SPDX spec 2.1: More expressive composite license expressions can be constructed using "OR", "AND", and "WITH" operators similar to constructing mathematical expressions using arithmetic operators. For the Tag:value format, any license expression that consists of more than one license identifier and/or LicenseRef, should be encapsulated by parentheses: "( )". > + > + A <SPDX License Expression> is either an SPDX short form license > + identifier found on the SPDX License List, or the combination of two > + SPDX short form license identifiers separated by "WITH" when a license > + exception applies. When multiple licenses apply, an expression consists > + of keywords "AND", "OR" separating sub-expressions and surrounded by > + "(", ")" . Conflicting with the example > + > + License identifiers for licenses like [L]GPL with the 'or later' option > + are constructed by using a "+" for indicating the 'or later' option.:: > + > + // SPDX-License-Identifier: GPL-2.0+ > + // SPDX-License-Identifier: LGPL-2.1+ > + > + WITH should be used when there is a modifier to a license needed. > + For example, the linux kernel UAPI files use the expression:: > + > + // SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note > + // SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note > + > + Other examples using WITH exceptions found in the kernel are:: > + > + // SPDX-License-Identifier: GPL-2.0 WITH mif-exception > + // SPDX-License-Identifier: GPL-2.0+ WITH GCC-exception-2.0 > + > + Exceptions can only be used with particular License identifiers. The > + valid License identifiers are listed in the tags of the exception text > + file. For details see the point `Exceptions`_ in the chapter `License > + identifiers`_. > + > + OR should be used if the file is dual licensed and only one license is > + to be selected. For example, some dtsi files are available under dual > + licenses:: > + > + // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause > + > + Examples from the kernel for license expressions in dual licensed files:: > + > + // SPDX-License-Identifier: GPL-2.0 OR MIT > + // SPDX-License-Identifier: GPL-2.0 OR BSD-2-Clause > + // SPDX-License-Identifier: GPL-2.0 OR Apache-2.0 > + // SPDX-License-Identifier: GPL-2.0 OR MPL-1.1 > + // SPDX-License-Identifier: (GPL-2.0 WITH Linux-syscall-note) OR MIT > + // SPDX-License-Identifier: GPL-1.0+ OR BSD-3-Clause OR OpenSSL > + > + AND should be used if the file has multiple licenses whose terms all > + apply to use the file. For example, if code is inherited from another > + project and permission has been given to put it in the kernel, but the > + original license terms need to remain in effect:: > + > + // SPDX-License-Identifier: (GPL-2.0 WITH Linux-syscall-note) AND MIT > + > + Another other example where both sets of license terms need to be > + adhered to is:: > + > + // SPDX-License-Identifier: GPL-1.0+ AND LGPL-2.1+ > +
