python*: set thread stack size on musl

Ensure recursion limit is reached before stack overflow.

Python does this for OSX and BSD:
https://github.com/python/cpython/blob/13ff24582c99dfb439b1af7295b401415e7eb05b/Python/thread_pthread.h#L22

Size of 1MB chosen to match value in Alpine:
https://git.alpinelinux.org/cgit/aports/commit/main/python2/APKBUILD?id=2f35283fec8ec451fe5fb477dd32ffdcc0776e89

Manual testing via Alpine's test-stacksize.py crashes on these
previously, and works with these changes.

pkgs/development/interpreters/python/cpython/2.7/default.nix

@@ -176,7 +176,8 @@ in stdenv.mkDerivation {
     LDFLAGS = stdenv.lib.optionalString (!stdenv.isDarwin) "-lgcc_s";
     inherit (mkPaths buildInputs) C_INCLUDE_PATH LIBRARY_PATH;
 
-    NIX_CFLAGS_COMPILE = optionalString stdenv.isDarwin "-msse2";
+    NIX_CFLAGS_COMPILE = optionalString stdenv.isDarwin "-msse2"
+      + optionalString hostPlatform.isMusl " -DTHREAD_STACK_SIZE=0x100000";
     DETERMINISTIC_BUILD = 1;
 
     setupHook = python-setup-hook sitePackages;

pkgs/development/interpreters/python/cpython/3.4/default.nix

@@ -105,6 +105,9 @@ in stdenv.mkDerivation {
     ${optionalString stdenv.isDarwin ''
        export NIX_CFLAGS_COMPILE="$NIX_CFLAGS_COMPILE -msse2"
        export MACOSX_DEPLOYMENT_TARGET=10.6
+     ''
+     + optionalString stdenv.hostPlatform.isMusl ''
+      export NIX_CFLAGS_COMPILE+=" -DTHREAD_STACK_SIZE=0x100000"
      ''}
   '';
 

pkgs/development/interpreters/python/cpython/3.5/default.nix

@@ -99,6 +99,9 @@ in stdenv.mkDerivation {
     ${optionalString stdenv.isDarwin ''
        export NIX_CFLAGS_COMPILE="$NIX_CFLAGS_COMPILE -msse2"
        export MACOSX_DEPLOYMENT_TARGET=10.6
+     ''
+     + optionalString stdenv.hostPlatform.isMusl ''
+      export NIX_CFLAGS_COMPILE+=" -DTHREAD_STACK_SIZE=0x100000"
      ''}
   '';
 

pkgs/development/interpreters/python/cpython/3.6/default.nix

@@ -122,6 +122,9 @@ in stdenv.mkDerivation {
     ${optionalString stdenv.isDarwin ''
        export NIX_CFLAGS_COMPILE="$NIX_CFLAGS_COMPILE -msse2"
        export MACOSX_DEPLOYMENT_TARGET=10.6
+     ''
+     + optionalString stdenv.hostPlatform.isMusl ''
+      export NIX_CFLAGS_COMPILE+=" -DTHREAD_STACK_SIZE=0x100000"
      ''}
   '';