From 6139195606d97b43a739500627c906baf804fab0 Mon Sep 17 00:00:00 2001 From: Brian Paul Date: Fri, 15 May 2015 11:22:25 -0600 Subject: [PATCH] mesa: fix glPushAttrib(0) / glPopAttrib() error If the glPushAttrib() mask value was zero we didn't actually push anything onto the attribute stack. A subsequent glPopAttrib() call would generate a GL_STACK_UNDERFLOW error. Now push a dummy attribute in that case to prevent the error. Mesa now matches nvidia's behavior. Reviewed-by: Jose Fonseca --- src/mesa/main/attrib.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/src/mesa/main/attrib.c b/src/mesa/main/attrib.c index b163c0aa699..365a79ded87 100644 --- a/src/mesa/main/attrib.c +++ b/src/mesa/main/attrib.c @@ -177,6 +177,10 @@ struct texture_state }; +/** An unused GL_*_BIT value */ +#define DUMMY_BIT 0x10000000 + + /** * Allocate new attribute node of given type/kind. Attach payload data. * Insert it into the linked list named by 'head'. @@ -253,6 +257,15 @@ _mesa_PushAttrib(GLbitfield mask) /* groups specified by the mask. */ head = NULL; + if (mask == 0) { + /* if mask is zero we still need to push something so that we + * don't get a GL_STACK_UNDERFLOW error in glPopAttrib(). + */ + GLuint dummy = 0; + if (!push_attrib(ctx, &head, DUMMY_BIT, sizeof(dummy), &dummy)) + goto end; + } + if (mask & GL_ACCUM_BUFFER_BIT) { if (!push_attrib(ctx, &head, GL_ACCUM_BUFFER_BIT, sizeof(struct gl_accum_attrib), @@ -928,6 +941,10 @@ _mesa_PopAttrib(void) } switch (attr->kind) { + case DUMMY_BIT: + /* do nothing */ + break; + case GL_ACCUM_BUFFER_BIT: { const struct gl_accum_attrib *accum; -- 2.30.2