From 60adbb477f9c5410aedade6b9d4eee74a4247eb2 Mon Sep 17 00:00:00 2001
From: Moraxyc <i@qaq.li>
Date: Sat, 3 Jan 2026 13:49:36 +0800
Subject: [PATCH] libretro.parallel-n64: fix build with gcc15

---
 .../emulators/libretro/cores/parallel-n64.nix |  8 +++
 .../cores/patches/parallel-n64-gcc15.patch    | 62 +++++++++++++++++++
 2 files changed, 70 insertions(+)
 create mode 100644 pkgs/applications/emulators/libretro/cores/patches/parallel-n64-gcc15.patch

diff --git a/pkgs/applications/emulators/libretro/cores/parallel-n64.nix b/pkgs/applications/emulators/libretro/cores/parallel-n64.nix
index a95a63558c1d..738804e10ae3 100644
--- a/pkgs/applications/emulators/libretro/cores/parallel-n64.nix
+++ b/pkgs/applications/emulators/libretro/cores/parallel-n64.nix
@@ -18,6 +18,14 @@ mkLibretroCore {
     hash = "sha256-Th8VqENewfTeRTH+lONN7ZTMLQ0G6901q6ZBNMgepL4=";
   };
 
+  patches = [
+    # Fix build with gcc15
+    # Upstream considers this core legacy (for "potato PC") and won't fix.
+    # See: https://github.com/libretro/parallel-n64/issues/797
+    #   /nix/store/...-glibc-2.40-66-dev/include/bits/mathcalls-narrow.h:36:20: error: conflicting types for 'fsqrt'; have 'float(double)'
+    ./patches/parallel-n64-gcc15.patch
+  ];
+
   extraBuildInputs = [
     libGLU
     libGL
diff --git a/pkgs/applications/emulators/libretro/cores/patches/parallel-n64-gcc15.patch b/pkgs/applications/emulators/libretro/cores/patches/parallel-n64-gcc15.patch
new file mode 100644
index 000000000000..52e0bc3e64ea
--- /dev/null
+++ b/pkgs/applications/emulators/libretro/cores/patches/parallel-n64-gcc15.patch
@@ -0,0 +1,62 @@
+From 3a891c0450c4968afbe76c594c22347354bd8834 Mon Sep 17 00:00:00 2001
+From: Moraxyc <i@qaq.li>
+Date: Sat, 3 Jan 2026 13:41:55 +0800
+Subject: [PATCH] Rename fsqrt to _fsqrt to avoid conflict
+
+---
+ mupen64plus-core/src/r4300/hacktarux_dynarec/assemble.h   | 2 +-
+ .../src/r4300/hacktarux_dynarec/hacktarux_dynarec.c       | 8 ++++----
+ 2 files changed, 5 insertions(+), 5 deletions(-)
+
+diff --git a/mupen64plus-core/src/r4300/hacktarux_dynarec/assemble.h b/mupen64plus-core/src/r4300/hacktarux_dynarec/assemble.h
+index 8161292..e256dd9 100644
+--- a/mupen64plus-core/src/r4300/hacktarux_dynarec/assemble.h
++++ b/mupen64plus-core/src/r4300/hacktarux_dynarec/assemble.h
+@@ -1650,7 +1650,7 @@ static INLINE void fchs(void)
+ }
+ 
+ 
+-static INLINE void fsqrt(void)
++static INLINE void _fsqrt(void)
+ {
+    put8(0xD9);
+    put8(0xFA);
+diff --git a/mupen64plus-core/src/r4300/hacktarux_dynarec/hacktarux_dynarec.c b/mupen64plus-core/src/r4300/hacktarux_dynarec/hacktarux_dynarec.c
+index 89fb982..2fc70d1 100644
+--- a/mupen64plus-core/src/r4300/hacktarux_dynarec/hacktarux_dynarec.c
++++ b/mupen64plus-core/src/r4300/hacktarux_dynarec/hacktarux_dynarec.c
+@@ -6317,13 +6317,13 @@ void gensqrt_d(void)
+ #ifdef __x86_64__
+    mov_xreg64_m64rel(RAX, (uint64_t *)(&reg_cop1_double[dst->f.cf.fs]));
+    fld_preg64_qword(RAX);
+-   fsqrt();
++   _fsqrt();
+    mov_xreg64_m64rel(RAX, (uint64_t *)(&reg_cop1_double[dst->f.cf.fd]));
+    fstp_preg64_qword(RAX);
+ #else
+    mov_eax_memoffs32((unsigned int *)(&reg_cop1_double[dst->f.cf.fs]));
+    fld_preg32_qword(EAX);
+-   fsqrt();
++   _fsqrt();
+    mov_eax_memoffs32((unsigned int *)(&reg_cop1_double[dst->f.cf.fd]));
+    fstp_preg32_qword(EAX);
+ #endif
+@@ -7301,13 +7301,13 @@ void gensqrt_s(void)
+ #ifdef __x86_64__
+    mov_xreg64_m64rel(RAX, (uint64_t *)(&reg_cop1_simple[dst->f.cf.fs]));
+    fld_preg64_dword(RAX);
+-   fsqrt();
++   _fsqrt();
+    mov_xreg64_m64rel(RAX, (uint64_t *)(&reg_cop1_simple[dst->f.cf.fd]));
+    fstp_preg64_dword(RAX);
+ #else
+    mov_eax_memoffs32((unsigned int *)(&reg_cop1_simple[dst->f.cf.fs]));
+    fld_preg32_dword(EAX);
+-   fsqrt();
++   _fsqrt();
+    mov_eax_memoffs32((unsigned int *)(&reg_cop1_simple[dst->f.cf.fd]));
+    fstp_preg32_dword(EAX);
+ #endif
+-- 
+2.52.0
+