Go release 1.18

Significant release with changes to language, toolchain, runtime, and libraries.

• Introduction of generics with type parameters.
• New syntax for function and type declarations.
• Parameterized functions and types.
• New 'any' and 'comparable' predeclared identifiers.

Mandatory to understand for writing and deploying generic code.

• Compiler now correctly reports 'declared but not used' errors.
• Reports overflow for rune constants in certain cases.

• New GOAMD64 environment variable.
• Support for 64-bit RISC-V architecture on Linux.
• Linux kernel version 2.6.32 or later required.
• Non-cooperative preemption support for Windows ARM and ARM64.
• iOS 12 or later required.

• Implementation of fuzzing.
• Changes to 'go get', 'go mod', 'go version', 'go work', 'go build', and 'go test'.
• Removal of +build lines in favor of //go:build lines.

• Garbage collector changes for predictable overhead.
• Efficient memory return to the operating system.
• Improved formatting of stack trace arguments.

• Passing function arguments and results using registers on more platforms.
• Inlining functions with range loops.
• New -asan compiler option.
• Possible 15% slower compile speed due to changes for generics.

Significant impact on performance and error messages.

• Fewer relocations for faster linking and smaller binaries.
• New -asan linker option.

Go 1.17 or later preferred for bootstrapping.

• New debug/buildinfo package.
• New net/netip package.
• TLS 1.2 default for client connections.
• Rejecting SHA-1 certificates.
• Various minor updates and performance improvements.