The patch above is wrong for if (!rc) last_err = rc;, the condition should be (rc).

It's in master (to be 1.12), then, it's backported to 1.11.2, which is confirmed build well.
So, closing.

Applied the change above.

I realized that I enbugged in rG5efabec21883: gpg:ecc: Use the common function of gnupg_get_ecc_params..
It has been regression since 2.5.9.

Pushed the changes in {gniibe/synch-spawn} branch.
It consists of three commits:

• rGb8b8afc5cf6f: build: Require libgpg-error 1.56 or newer.
• rG15b8bc7495db: w32: Synchronous spawning gpg-agent/dirmngr/keyboxd.
• rG6bd6826aa6ff: common:w32: Care about the NUL device for start_new_service.

In T7642#203189, @gniibe wrote:

I wonder about GCC 15 preparation for the release. If it's good to have, three patches are needed to apply:

I pushed the longlong patch: rCb61a7661d017: mpi: Provide the function prototype of __udiv_qrnnd.

IIUC, it's actually binutils version dependency (instead of GCC 15), perhaps.

I wonder about GCC 15 preparation for the release. If it's good to have, two patches are needed to apply:

• Cherry-picking rCd5fb7cd9b351: Mark nonstring use cases with __nonstring__ attribute.
• Apply changes of T7721: libgcrypt build-error with gcc-15 on powerpc and alpha

I figured out that .machine "any" is needed with GCC 15.

For Alpha (hppa, and sparc), IIUC, following patch may help:

For PowerISA 3.00 Instructions issue, following patch may help:

Here is a patch.

diff --git a/agent/divert-scd.c b/agent/divert-scd.c
index 1e5de4671..bb42dd3b4 100644
--- a/agent/divert-scd.c
+++ b/agent/divert-scd.c
@@ -517,6 +517,9 @@ agent_card_ecc_kem (ctrl_t ctrl, const unsigned char *ecc_ct,

Fixed with new GPGRT_PROCESS_STDIO_NUL flag.

Pushed the changes:

• Inheriting HANDLEs has been not working accurately
  • Before the fix, all HANDLEs were inherited
  • Only specified HANDLEs are inherited by: rE0b01950237ab: w32:spawn: Fix inheriting HANDLEs.
• HANDLEs by w32_open_null were leaked
  • fixed by: rEf28bf71b86ba: w32:spawn: Fix resource leaks for HANDLEs by w32_open_null.

T7723 fix by rE311fb769d1dd: w32:spawn: New flag GPGRT_PROCESS_STDIO_NUL.

Before implementing this feature, it's better to fix T7723: gpgrt:w32: Fix for inheriting stdin/stdout/stderr with "NUL", and do some clean up.

If we will fix gpgconf using GPGRT_PROCESS_IO_NUL, we will need to fix gpg-connect-agent to see if it's NUL or not.

Here is an experimental change to support the feature.

I'm testing the following patch with experimental change of libgpg-error.

In libgpg-error, we have: rE65114f24e13f: w32: More changes to the extended length path handling.

Fixed in 2.5.8.

secp256k1 failure:
https://lists.gnupg.org/pipermail/gnupg-users/2025-June/067731.html