diff --git a/cpu.cpp b/cpu.cpp
index 95561742..da9f298c 100644
--- a/cpu.cpp
+++ b/cpu.cpp
@@ -72,9 +72,8 @@ extern "C" {
 extern "C"
 {
 	static jmp_buf s_jmpNoCPUID;
-	static void SigIllHandlerCPUID(int unused)
+	static void SigIllHandler(int)
 	{
-		CRYPTOPP_UNUSED(unused);
 		longjmp(s_jmpNoCPUID, 1);
 	}
 }
@@ -358,14 +357,17 @@ bool CpuId(word32 func, word32 subfunc, word32 output[4])
 	// http://github.com/weidai11/cryptopp/issues/24 and http://stackoverflow.com/q/7721854
 	volatile bool result = true;
 
-	volatile SigHandler oldHandler = signal(SIGILL, SigIllHandlerCPUID);
+	volatile SigHandler oldHandler = signal(SIGILL, SigIllHandler);
 	if (oldHandler == SIG_ERR)
 		return false;
 
 # ifndef __MINGW32__
 	volatile sigset_t oldMask;
 	if (sigprocmask(0, NULLPTR, (sigset_t*)&oldMask) != 0)
+	{
+		signal(SIGILL, oldHandler);
 		return false;
+	}
 # endif
 
 	if (setjmp(s_jmpNoCPUID))
diff --git a/crc_simd.cpp b/crc_simd.cpp
index 35509335..93ab9bc9 100644
--- a/crc_simd.cpp
+++ b/crc_simd.cpp
@@ -87,7 +87,10 @@ bool CPU_ProbeCRC32()
 
     volatile sigset_t oldMask;
     if (sigprocmask(0, NULLPTR, (sigset_t*)&oldMask))
+    {
+        signal(SIGILL, oldHandler);
         return false;
+    }
 
     if (setjmp(s_jmpSIGILL))
         result = false;
diff --git a/gcm_simd.cpp b/gcm_simd.cpp
index ef9e2ebf..c8375f5c 100644
--- a/gcm_simd.cpp
+++ b/gcm_simd.cpp
@@ -123,7 +123,10 @@ bool CPU_ProbePMULL()
 
     volatile sigset_t oldMask;
     if (sigprocmask(0, NULLPTR, (sigset_t*)&oldMask))
+    {
+        signal(SIGILL, oldHandler);
         return false;
+    }
 
     if (setjmp(s_jmpSIGILL))
         result = false;
@@ -174,7 +177,10 @@ bool CPU_ProbePMULL()
 
     volatile sigset_t oldMask;
     if (sigprocmask(0, NULLPTR, (sigset_t*)&oldMask))
+    {
+        signal(SIGILL, oldHandler);
         return false;
+    }
 
     if (setjmp(s_jmpSIGILL))
         result = false;
diff --git a/neon_simd.cpp b/neon_simd.cpp
index 12473d99..602ba0e9 100644
--- a/neon_simd.cpp
+++ b/neon_simd.cpp
@@ -77,7 +77,10 @@ bool CPU_ProbeARMv7()
 
     volatile sigset_t oldMask;
     if (sigprocmask(0, NULLPTR, (sigset_t*)&oldMask))
+    {
+        signal(SIGILL, oldHandler);
         return false;
+    }
 
     if (setjmp(s_jmpSIGILL))
         result = false;
@@ -160,7 +163,10 @@ bool CPU_ProbeNEON()
 
     volatile sigset_t oldMask;
     if (sigprocmask(0, NULLPTR, (sigset_t*)&oldMask))
+    {
+        signal(SIGILL, oldHandler);
         return false;
+    }
 
     if (setjmp(s_jmpSIGILL))
         result = false;
@@ -176,7 +182,7 @@ bool CPU_ProbeNEON()
         uint32x4_t y = vshlq_n_u32(x, 4);
 
         word32 z[4]; vst1q_u32(z, y);
-        return (z[0] & z[1] & z[2] & z[3]) == 16;
+        result = (z[0] & z[1] & z[2] & z[3]) == 16;
     }
 
     sigprocmask(SIG_SETMASK, (sigset_t*)&oldMask, NULLPTR);
diff --git a/ppc_power7.cpp b/ppc_power7.cpp
index 49c97cee..84a7275a 100644
--- a/ppc_power7.cpp
+++ b/ppc_power7.cpp
@@ -55,7 +55,10 @@ bool CPU_ProbePower7()
 
     volatile sigset_t oldMask;
     if (sigprocmask(0, NULLPTR, (sigset_t*)&oldMask))
+    {
+        signal(SIGILL, oldHandler);
         return false;
+    }
 
     if (setjmp(s_jmpSIGILL))
         result = false;
diff --git a/ppc_power8.cpp b/ppc_power8.cpp
index 7ed65ebb..7e287ee5 100644
--- a/ppc_power8.cpp
+++ b/ppc_power8.cpp
@@ -56,7 +56,10 @@ bool CPU_ProbePower8()
 
     volatile sigset_t oldMask;
     if (sigprocmask(0, NULLPTR, (sigset_t*)&oldMask))
+    {
+        signal(SIGILL, oldHandler);
         return false;
+    }
 
     if (setjmp(s_jmpSIGILL))
         result = false;
@@ -109,7 +112,10 @@ bool CPU_ProbeAES()
 
     volatile sigset_t oldMask;
     if (sigprocmask(0, NULLPTR, (sigset_t*)&oldMask))
+    {
+        signal(SIGILL, oldHandler);
         return false;
+    }
 
     if (setjmp(s_jmpSIGILL))
         result = false;
@@ -158,7 +164,10 @@ bool CPU_ProbeSHA256()
 
     volatile sigset_t oldMask;
     if (sigprocmask(0, NULLPTR, (sigset_t*)&oldMask))
+    {
+        signal(SIGILL, oldHandler);
         return false;
+    }
 
     if (setjmp(s_jmpSIGILL))
         result = false;
@@ -202,7 +211,10 @@ bool CPU_ProbeSHA512()
 
     volatile sigset_t oldMask;
     if (sigprocmask(0, NULLPTR, (sigset_t*)&oldMask))
+    {
+        signal(SIGILL, oldHandler);
         return false;
+    }
 
     if (setjmp(s_jmpSIGILL))
         result = false;
diff --git a/ppc_power9.cpp b/ppc_power9.cpp
index c842d46d..8870023f 100644
--- a/ppc_power9.cpp
+++ b/ppc_power9.cpp
@@ -55,7 +55,10 @@ bool CPU_ProbePower9()
 
     volatile sigset_t oldMask;
     if (sigprocmask(0, NULLPTR, (sigset_t*)&oldMask))
+    {
+        signal(SIGILL, oldHandler);
         return false;
+    }
 
     if (setjmp(s_jmpSIGILL))
         result = false;
@@ -102,7 +105,10 @@ bool CPU_ProbeDARN()
 
     volatile sigset_t oldMask;
     if (sigprocmask(0, NULLPTR, (sigset_t*)&oldMask))
+    {
+        signal(SIGILL, oldHandler);
         return false;
+    }
 
     if (setjmp(s_jmpSIGILL))
         result = false;
diff --git a/ppc_simd.cpp b/ppc_simd.cpp
index b8182ad5..081d0515 100644
--- a/ppc_simd.cpp
+++ b/ppc_simd.cpp
@@ -58,7 +58,10 @@ bool CPU_ProbeAltivec()
 
     volatile sigset_t oldMask;
     if (sigprocmask(0, NULLPTR, (sigset_t*)&oldMask))
+    {
+        signal(SIGILL, oldHandler);
         return false;
+    }
 
     if (setjmp(s_jmpSIGILL))
         result = false;
diff --git a/rijndael_simd.cpp b/rijndael_simd.cpp
index c40df9c6..b7f830f4 100644
--- a/rijndael_simd.cpp
+++ b/rijndael_simd.cpp
@@ -118,7 +118,10 @@ bool CPU_ProbeAES()
 
     volatile sigset_t oldMask;
     if (sigprocmask(0, NULLPTR, (sigset_t*)&oldMask))
+    {
+        signal(SIGILL, oldHandler);
         return false;
+    }
 
     if (setjmp(s_jmpSIGILL))
         result = false;
diff --git a/sha_simd.cpp b/sha_simd.cpp
index 419e183b..277c9362 100644
--- a/sha_simd.cpp
+++ b/sha_simd.cpp
@@ -113,7 +113,10 @@ bool CPU_ProbeSHA1()
 
     volatile sigset_t oldMask;
     if (sigprocmask(0, NULLPTR, (sigset_t*)&oldMask))
+    {
+        signal(SIGILL, oldHandler);
         return false;
+    }
 
     if (setjmp(s_jmpSIGILL))
         result = false;
@@ -180,7 +183,10 @@ bool CPU_ProbeSHA256()
 
     volatile sigset_t oldMask;
     if (sigprocmask(0, NULLPTR, (sigset_t*)&oldMask))
+    {
+        signal(SIGILL, oldHandler);
         return false;
+    }
 
     if (setjmp(s_jmpSIGILL))
         result = false;
diff --git a/sse_simd.cpp b/sse_simd.cpp
index bd4d59c2..96c80a27 100644
--- a/sse_simd.cpp
+++ b/sse_simd.cpp
@@ -34,7 +34,7 @@ extern const char SSE_SIMD_FNAME[] = __FILE__;
 
 NAMESPACE_BEGIN(CryptoPP)
 
-#ifndef CRYPTOPP_MS_STYLE_INLINE_ASSEMBLY
+#ifdef CRYPTOPP_GNU_STYLE_INLINE_ASSEMBLY
 extern "C" {
     typedef void (*SigHandler)(int);
 }
@@ -42,12 +42,12 @@ extern "C" {
 extern "C"
 {
     static jmp_buf s_jmpNoSSE2;
-    static void SigIllHandlerSSE2(int)
+    static void SigIllHandler(int)
     {
         longjmp(s_jmpNoSSE2, 1);
     }
 }
-#endif  // Not CRYPTOPP_MS_STYLE_INLINE_ASSEMBLY
+#endif  // CRYPTOPP_GNU_STYLE_INLINE_ASSEMBLY
 
 bool CPU_ProbeSSE2()
 {
@@ -78,14 +78,17 @@ bool CPU_ProbeSSE2()
     // http://github.com/weidai11/cryptopp/issues/24 and http://stackoverflow.com/q/7721854
     volatile bool result = true;
 
-    volatile SigHandler oldHandler = signal(SIGILL, SigIllHandlerSSE2);
+    volatile SigHandler oldHandler = signal(SIGILL, SigIllHandler);
     if (oldHandler == SIG_ERR)
         return false;
 
 # ifndef __MINGW32__
     volatile sigset_t oldMask;
     if (sigprocmask(0, NULLPTR, (sigset_t*)&oldMask))
+    {
+        signal(SIGILL, oldHandler);
         return false;
+    }
 # endif
 
     if (setjmp(s_jmpNoSSE2))