diff --git a/resources/lib/std/cinterop.c3 b/resources/lib/std/cinterop.c3
index 4259d8603..9df255e46 100644
--- a/resources/lib/std/cinterop.c3
+++ b/resources/lib/std/cinterop.c3
@@ -71,7 +71,8 @@ $endif;
 define CSChar = ichar;
 define CUChar = char;
 
-/*
-define CChar = ${C_CHAR_TYPE};
-define CSChar = ${C_SCHAR_TYPE};
-*/
+$if (${C_CHAR_IS_SIGNED}):
+    define CChar = ichar;
+$else:
+    define CChar = char;
+$endif;
diff --git a/src/compiler/compiler.c b/src/compiler/compiler.c
index 30a9be8d9..8f70ff7a6 100644
--- a/src/compiler/compiler.c
+++ b/src/compiler/compiler.c
@@ -279,6 +279,7 @@ void compiler_compile(void)
 	setup_int_define("C_INT_SIZE", platform_target.width_c_int);
 	setup_int_define("C_LONG_SIZE", platform_target.width_c_long);
 	setup_int_define("C_LONG_LONG_SIZE", platform_target.width_c_long_long);
+	setup_bool_define("C_CHAR_IS_SIGNED", platform_target.signed_c_char);
 	setup_bool_define("PLATFORM_LITTLE_ENDIAN", platform_target.little_endian);
 	setup_bool_define("PLATFORM_I128_SUPPORTED", platform_target.int128);
 	setup_int_define("COMPILER_OPT_LEVEL", (int)active_target.optimization_level);
diff --git a/src/compiler/target.c b/src/compiler/target.c
index 955a96c9e..8b54e1617 100644
--- a/src/compiler/target.c
+++ b/src/compiler/target.c
@@ -20,6 +20,7 @@ static unsigned os_target_supports_float128(OsType os, ArchType arch);
 static unsigned os_target_supports_vec(OsType os, ArchType arch, int bits, bool is_int);
 static bool os_requires_libc(OsType os);
 
+
 PlatformTarget platform_target = {};
 
 int target_alloca_addr_space()
@@ -207,6 +208,34 @@ static inline bool os_is_apple(OsType os_type)
 	       os_type == OS_TYPE_MACOSX || os_type == OS_TYPE_IOS;
 }
 
+static bool os_target_signed_c_char_type(OsType os, ArchType arch)
+{
+	switch (arch)
+	{
+		case ARCH_TYPE_AARCH64:
+		case ARCH_TYPE_AARCH64_32:
+		case ARCH_TYPE_AARCH64_BE:
+		case ARCH_TYPE_ARM:
+		case ARCH_TYPE_ARMB:
+		case ARCH_TYPE_THUMB:
+		case ARCH_TYPE_THUMBEB:
+			if (os_is_apple(os) || os == OS_TYPE_WIN32) return true;
+			return false;
+		case ARCH_TYPE_PPC:
+		case ARCH_TYPE_PPC64:
+			return os_is_apple(os);
+		case ARCH_TYPE_HEXAGON:
+		case ARCH_TYPE_PPC64LE:
+		case ARCH_TYPE_RISCV32:
+		case ARCH_TYPE_RISCV64:
+		case ARCH_TYPE_SYSTEMZ:
+		case ARCH_TYPE_XCORE:
+			return false;
+		default:
+			return true;
+	}
+}
+
 static inline void target_setup_arm_abi(void)
 {
 	platform_target.abi = ABI_ARM;
@@ -1197,7 +1226,7 @@ void target_setup(BuildTarget *target)
 	platform_target.width_c_int = os_target_c_type_bits(platform_target.os, platform_target.arch, CTYPE_INT);
 	platform_target.width_c_long = os_target_c_type_bits(platform_target.os, platform_target.arch, CTYPE_LONG);
 	platform_target.width_c_long_long = os_target_c_type_bits(platform_target.os, platform_target.arch, CTYPE_LONG_LONG);
-
+	platform_target.signed_c_char = os_target_signed_c_char_type(platform_target.os, platform_target.arch);
 
 	/**
 	 * x86-64: CMOV, CMPXCHG8B, FPU, FXSR, MMX, FXSR, SCE, SSE, SSE2
@@ -1307,3 +1336,4 @@ void target_setup(BuildTarget *target)
 		// TODO remove
 	type_setup(&platform_target);
 }
+
diff --git a/src/compiler/target.h b/src/compiler/target.h
index dae60a448..5646729e1 100644
--- a/src/compiler/target.h
+++ b/src/compiler/target.h
@@ -249,6 +249,7 @@ typedef struct
 	PicGeneration pic : 3;
 	PieGeneration pie : 3;
 	bool pic_required : 1;
+	bool signed_c_char : 1;
 	FloatABI float_abi : 3;
 	unsigned default_number_regs_x86 : 8;
 	union