add CI for GP2X also

no helix as it has (had?) weird license IIRC

.github/workflows/ci-gp2x.yml

@@ -0,0 +1,20 @@
+name: CI (GP2X)
+on: [push, pull_request]
+jobs:
+  build-linux:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+      with:
+        submodules: true
+    - name: Install dependencies
+      run: |
+        whoami
+        sudo apt-get update -qq
+        sudo apt-get install -y wget
+        wget http://notaz.gp2x.de/downloads/gp2x/devkitGP2X_small.tar.xz
+        tar -C /tmp/ -xf devkitGP2X_small.tar.xz
+    - name: configure
+      run: DUMP_CONFIG_LOG=1 PATH=$PATH:/tmp/devkitGP2X/bin CROSS_COMPILE=arm-linux- ./configure --platform=gp2x
+    - name: make
+      run: PATH=$PATH:/tmp/devkitGP2X/bin CROSS_COMPILE=arm-linux- make PLATFORM_MP3=0

Makefile

@@ -61,14 +61,15 @@ chkCCflag = $(shell n=/dev/null; echo $(1) | tr " " "\n" | while read f; do \
 
 ifeq ("$(PLATFORM)",$(filter "$(PLATFORM)","gp2x" "opendingux" "miyoo" "rpi1"))
 # very small caches, avoid optimization options making the binary much bigger
-CFLAGS += -fno-common -fno-stack-protector -finline-limit=42 -fno-unroll-loops -ffast-math
+CFLAGS += -fno-common -finline-limit=42 -fno-unroll-loops -ffast-math
+CFLAGS += $(call chkCCflag, -fno-stack-protector)
 ifneq ($(call chkCCflag, -fipa-ra),) # gcc >= 5
 CFLAGS += $(call chkCCflag, -flto -fipa-pta -fipa-ra)
 else
 # these improve execution speed on 32bit arm/mips with gcc pre-5 toolchains
-CFLAGS += -fno-ipa-cp -fno-caller-saves -fno-guess-branch-probability -fno-regmove
+CFLAGS += -fno-caller-saves -fno-guess-branch-probability -fno-regmove
 # very old gcc toolchains may not have these options
-CFLAGS += $(call chkCCflag, -fno-tree-loop-if-convert -fipa-pta)
+CFLAGS += $(call chkCCflag, -fno-tree-loop-if-convert -fipa-pta -fno-ipa-cp)
 endif
 endif
 

platform/common/mp3_drmp3.c

@@ -16,6 +16,10 @@
 #define _wfopen_s(p,m)	NULL
 #define _wfopen(p,m)	NULL
 #endif
+#ifdef __GP2X__
+#define mp3dec_decode _mp3dec_decode
+#define mp3dec_start _mp3dec_start
+#endif
 #define DR_MP3_IMPLEMENTATION
 #include "dr_libs/dr_mp3.h"
 #include "mp3.h"