diff --git a/contrib/riscv-rvv/linux.c b/contrib/riscv-rvv/linux.c
index 9babc09be..c3a0ff808 100644
--- a/contrib/riscv-rvv/linux.c
+++ b/contrib/riscv-rvv/linux.c
@@ -25,7 +25,7 @@
 #endif
 
 static int
-png_have_rvv(png_structp png_ptr) {
+png_have_rvv() {
 #if defined(__linux__)
    return getauxval (AT_HWCAP) & COMPAT_HWCAP_ISA_V ? 1 : 0;
 #else
diff --git a/riscv/riscv_init.c b/riscv/riscv_init.c
index f3d92150d..1d9982436 100644
--- a/riscv/riscv_init.c
+++ b/riscv/riscv_init.c
@@ -26,7 +26,7 @@
 #  endif
 #endif
 
-static int png_have_rvv(png_structp png_ptr);
+static int png_have_rvv();
 #ifdef PNG_RISCV_RVV_FILE
 #  include PNG_RISCV_RVV_FILE
 #endif
@@ -43,7 +43,7 @@ png_init_filter_functions_rvv(png_structp pp, unsigned int bpp)
    static volatile sig_atomic_t no_rvv = -1; /* not checked */
 
    if (no_rvv < 0)
-      no_rvv = !png_have_rvv(pp);
+      no_rvv = !png_have_rvv();
 
    if (no_rvv)
       return;