tree 6c51bb856204080df9e039f6172c9072837f79ff
parent 382e68c6db30e7061e5898c14574aed4c9be7079
author Nico Weber <thakis@chromium.org> 1773074632 -0400
committer GN LUCI <gn-scoped@luci-project-accounts.iam.gserviceaccount.com> 1773329373 -0700

Reject newlines in string config values (defines, cflags, etc.)

A literal newline in a define or flag value would be written verbatim
into ninja files, breaking ninja's line-based parsing. Rather than
trying to escape newlines (which would work on POSIX via $$'\n' but
has no equivalent for cmd.exe on Windows), reject them with a clear
error at GN time. A newline in a compiler flag is almost certainly
a mistake anyway.

The validation is in GetStringList() so it covers all string config
values: defines, cflags, cflags_c, cflags_cc, cflags_objc,
cflags_objcc, asmflags, arflags, ldflags, rustflags, rustenv, and
swiftflags.

Before, without the pkg-config.py change in the linked bug, things
failed at build time:

```
% autoninja -C out/gnlinux  base_unittests
offline mode
ninja: Entering directory `out/gnlinux'
 0.20s load build.ninja failed:

 1.47s Error: failed to load build.ninja: toolchain.ninja: line:61052: unexpected indent: "  include_dirs =
```

Now, the fail at `gn gen` time instead:

```
% ~/src/gn/out/gn gen out/gnlinux
//build/config/linux/pkg-config.py ["-s", "../../build/linux/debian_bullseye_amd64-sysroot", "-a", "x64"] []
ERROR at //build/config/linux/atk/BUILD.gn:33:5: Newlines in defines values are not supported.
    "ATK_LIB_DIR=\"$atk_lib_dir\"",
    ^-----------------------------
The value `ATK_LIB_DIR="[[],[],[],[],[]]
"` contains a newline.
See //build/config/linux/atk/BUILD.gn:19:1: whence it was called.
pkg_config("atk") {
^------------------
See //ui/accessibility/BUILD.gn:465:20: which caused the file to be included.
      configs += [ "//build/config/linux/atk" ]
                   ^-------------------------
```

Bug: 40176116
Change-Id: I870d625552087430f5a679b8668a1929662e7b4a
Reviewed-on: https://gn-review.googlesource.com/c/gn/+/21460
Reviewed-by: Takuto Ikuta <tikuta@google.com>
Commit-Queue: Nico Weber <thakis@chromium.org>
Reviewed-by: Nico Weber <thakis@google.com>