Only apply linker strip optimizations in release builds

Otherwise, debugging is impeded.

BUILD

@@ -48,6 +48,26 @@ config_setting(
     flag_values = {":py-limited-api": "unset"},
 )
 
+config_setting(
+    name = "MacReleaseBuild",
+    constraint_values = [
+        "@platforms//os:macos",
+    ],
+    values = {
+        "compilation_mode": "opt",
+    },
+)
+
+config_setting(
+    name = "LinuxReleaseBuild",
+    constraint_values = [
+        "@platforms//os:linux",
+    ],
+    values = {
+        "compilation_mode": "opt",
+    },
+)
+
 selects.config_setting_group(
     name = "unix",
     match_any = [

helpers.bzl

@@ -7,6 +7,14 @@ def sizeopts():
         "@nanobind_bazel//:without_sizeopts": [],
     })
 
+def stripopts():
+    """Linker options to strip external and debug symbols from nanobind release builds."""
+    return select({
+        "@nanobind_bazel//:MacReleaseBuild": ["-Wl,-x", "-Wl,-S"],
+        "@nanobind_bazel//:LinuxReleaseBuild": ["-Wl,-s"],
+        "//conditions:default": [],
+    })
+
 def sizedefs():
     return select({
         "@nanobind_bazel//:with_sizeopts": ["NB_COMPACT_ASSERTIONS"],

nanobind.BUILD

@@ -5,7 +5,7 @@ Size optimizations used: -Os, LTO.
 Linker optimizations used: LTO (clang, gcc) / LTCG (MSVC), linker response file (macOS only).
 """
 
-load("@nanobind_bazel//:helpers.bzl", "py_limited_api", "sizedefs", "sizeopts")
+load("@nanobind_bazel//:helpers.bzl", "py_limited_api", "sizedefs", "sizeopts", "stripopts")
 
 licenses(["notice"])
 
@@ -37,19 +37,14 @@ cc_library(
     features = ["-pic"],  # use a compiler flag instead.
     includes = ["include"],
     linkopts = select({
-        "@platforms//os:linux": [
-            "-Wl,-s",
-            "-Wl,--gc-sections",
-        ],
+        "@platforms//os:linux": ["-Wl,--gc-sections"],
         "@platforms//os:macos": [
             # chained fixups on Apple platforms.
             "-Wl,@$(location :cmake/darwin-ld-cpython.sym)",
             "-Wl,-dead_strip",
-            "-Wl,-x",
-            "-Wl,-S",
         ],
         "//conditions:default": [],
-    }),
+    }) + stripopts(),
     local_defines = sizedefs(),  # sizeopts apply to nanobind only.
     textual_hdrs = glob(
         [