The build system knows how to deal with lex files, but it treats them as c++, so make spec.lex

conform to that.

libs/rs/Android.mk

@@ -14,17 +14,8 @@ LOCAL_IS_HOST_MODULE := true
 LOCAL_MODULE_CLASS := EXECUTABLES
 intermediates := $(local-intermediates-dir)
 
-GEN := $(addprefix $(intermediates)/, \
-            lex.yy.c \
-        )
-$(GEN):	PRIVATE_CUSTOM_TOOL = flex -o $@ $<
-
-$(intermediates)/lex.yy.c : $(LOCAL_PATH)/spec.lex
-	$(transform-generated-source)
-
-$(LOCAL_PATH)/rsg_generator.c : $(intermediates)/lex.yy.c
-
 LOCAL_SRC_FILES:= \
+    spec.l \
     rsg_generator.c
 
 include $(BUILD_HOST_EXECUTABLE)

libs/rs/rsg_generator.c

@@ -1,6 +1,6 @@
 
-
-#include "lex.yy.c"
+#include "spec.h"
+#include <stdio.h>
 
 void printFileHeader(FILE *f)
 {
@@ -45,7 +45,7 @@ void printVarType(FILE *f, const VarType *vt)
             fprintf(f, "double");
         break;
     case 4:
-        fprintf(f, "%s", vt->typename);
+        fprintf(f, "%s", vt->typeName);
         break;
     }
 
@@ -157,7 +157,7 @@ void printApiCpp(FILE *f)
             needFlush += vt->ptrLevel;
             fprintf(f, "    cmd->%s = %s;\n", vt->name, vt->name);
         }
-        if (api->ret.typename[0]) {
+        if (api->ret.typeName[0]) {
             needFlush = 1;
         }
 
@@ -167,7 +167,7 @@ void printApiCpp(FILE *f)
         }
         fprintf(f, "(RS_CMD_ID_%s, size);\n", api->name);
 
-        if (api->ret.typename[0]) {
+        if (api->ret.typeName[0]) {
             fprintf(f, "    return reinterpret_cast<");
             printVarType(f, &api->ret);
             fprintf(f, ">(io->mToCoreRet);\n");
@@ -199,7 +199,7 @@ void printPlaybackCpp(FILE *f)
         //fprintf(f, "    LOGE(\"play command %s\\n\");\n", api->name);
         fprintf(f, "    const RS_CMD_%s *cmd = static_cast<const RS_CMD_%s *>(vp);\n", api->name, api->name);
         fprintf(f, "    ");
-        if (api->ret.typename[0]) {
+        if (api->ret.typeName[0]) {
             fprintf(f, "gIO->mToCoreRet = (intptr_t)");
         }
         fprintf(f, "rsi_%s(con", api->name);

libs/rs/spec.h

@@ -0,0 +1,38 @@
+#ifndef SPEC_H
+#define SPEC_H
+
+#if __cplusplus
+extern "C" {
+#endif
+
+extern int num_lines;
+
+typedef struct {
+  int isConst;
+  int type;
+  int bits;
+  int ptrLevel;
+  char name[256];
+  char typeName[256];
+} VarType;
+
+extern VarType *currType;
+
+typedef struct {
+  char name[256];
+  int sync;
+  int paramCount;
+  VarType ret;
+  VarType params[16];
+} ApiEntry;
+
+extern ApiEntry apis[128];
+extern int apiCount;
+
+extern int typeNextState;
+
+#if __cplusplus
+} // extern "C"
+#endif
+
+#endif // SPEC_H

libs/rs/spec.l

@@ -9,33 +9,19 @@
 DIGIT    [0-9]
 ID       [a-zA-Z_][a-zA-Z0-9_]*
 
+    #include "spec.h"
 
    int num_lines = 0;
 
-   typedef struct {
-      int isConst;
-      int type;
-      int bits;
-      int ptrLevel;
-      char name[256];
-      char typename[256];
-   } VarType;
-
    VarType *currType = 0;
 
-   typedef struct {
-      char name[256];
-      int sync;
-      int paramCount;
-      VarType ret;
-      VarType params[16];
-   } ApiEntry;
-
    ApiEntry apis[128];
    int apiCount = 0;
 
    int typeNextState;
 
+   extern "C" int yylex();
+
 %%
 
 "/*"         BEGIN(comment);
@@ -141,7 +127,7 @@ ID       [a-zA-Z_][a-zA-Z0-9_]*
 <var_type>{ID} {
     currType->type = 4;
     currType->bits = 32;
-    memcpy(currType->typename, yytext, yyleng);
+    memcpy(currType->typeName, yytext, yyleng);
     BEGIN(typeNextState);
     }