The --export-compile-commands option for build-webkit is broken.

https://bugs.webkit.org/show_bug.cgi?id=264239

Reviewed by Elliott Williams.

The build-webkit with --export-compile-commands on macOS does not produce
compile_commands.json. In bug 235686 [1], we added the support of exporting
compile_commands.json to the make build. This change brings the same
support into the build-webkit script.

[1] https://webkit.org/b/235686

* Tools/Scripts/build-webkit:
* Tools/Scripts/webkitdirs.pm:
(XcodeExportCompileCommandsOptions):
* Tools/Scripts/webkitperl/BuildSubproject.pm:

Canonical link: https://commits.webkit.org/270348@main

Tools/Scripts/build-webkit

@@ -351,6 +351,7 @@ if (isWinCairo() || isPlayStation()) {
     push @local_options, XcodeCoverageSupportOptions() if $coverageSupport;
     push @local_options, XcodeStaticAnalyzerOption() if $shouldRunStaticAnalyzer;
     push @local_options, "WK_LTO_MODE=$ltoMode" if ($ltoMode ne "default");
+    push @local_options, XcodeExportCompileCommandsOptions() if $exportCompileCommands;
     # FIXME: Move this setting to xcconfigs once all local Xcode builds of WebKit
     # happen in the workspace. When this is only passed on the command line, it
     # invalidates build results made in the IDE (rdar://88135402).

Tools/Scripts/webkitdirs.pm

@@ -63,6 +63,7 @@ BEGIN {
    @ISA         = qw(Exporter);
    @EXPORT      = qw(
        &XcodeCoverageSupportOptions
+       &XcodeExportCompileCommandsOptions
        &XcodeOptionString
        &XcodeOptionStringNoConfig
        &XcodeOptions
@@ -1294,6 +1295,11 @@ sub XcodeCoverageSupportOptions()
     return ("-xcconfig", sourceDir() . "/Tools/coverage/coverage.xcconfig");
 }
 
+sub XcodeExportCompileCommandsOptions()
+{
+    return ("OTHER_CFLAGS=\$(inherited) -gen-cdb-fragment-path \$(BUILT_PRODUCTS_DIR)/compile_commands", "GCC_PRECOMPILE_PREFIX_HEADER=NO", "CLANG_ENABLE_MODULE_DEBUGGING=NO", "COMPILER_INDEX_STORE_ENABLE=NO");
+}
+
 sub XcodeStaticAnalyzerOption()
 {
     return "RUN_CLANG_STATIC_ANALYZER=YES";

Tools/Scripts/webkitperl/BuildSubproject.pm

@@ -198,6 +198,7 @@ if (isAppleCocoaWebKit()) {
     my @additionalSupportOptions = ();
     push @additionalSupportOptions, XcodeCoverageSupportOptions() if $coverageSupport;
     push @additionalSupportOptions, XcodeStaticAnalyzerOption() if $shouldRunStaticAnalyzer;
+    push @additionalSupportOptions, XcodeExportCompileCommandsOptions() if $exportCompileCommands;
 
     push @options, ($forceCLoop ? "ENABLE_JIT=ENABLE_JIT=0" : "ENABLE_JIT=ENABLE_JIT");
     push @options, ($forceCLoop ? "ENABLE_C_LOOP=ENABLE_C_LOOP" : "ENABLE_C_LOOP=ENABLE_C_LOOP=0");